ASSOC Displays or modifies file extension associations.
ATTRIB Displays or changes file attributes.
BREAK Sets or clears extended CTRL+C checking.
*BCDEDIT Sets properties in boot database to control boot loading.
CACLS Displays or modifies access control lists (ACLs) of files.
CALL Calls one batch program from another.
CD Displays the name of or changes the current directory.
CHCP Displays or sets the active code page number.
CHDIR Displays the name of or changes the current directory.
CHKDSK Checks a disk and displays a status report.
CHKNTFS Displays or modifies the checking of disk at boot time.
*CHOICE Batch file command that allows users to select from a set of options.
CIPHER Displays or alters the encryption of directories [files] on NTFS partitions.
*CLIP Redirects output of another command to the Windows clipboard.
CLS Clears the screen.
CMD Starts a new instance of the Windows command interpreter.
*CMDKEY Creates, lists and deletes stored user names and passwords or credentials.
COLOR Sets the default console foreground and background colors.
COMP Compares the contents of two files or sets of files.
COMPACT Displays or alters the compression of files on NTFS partitions.
CONVERT Converts FAT volumes to NTFS. You cannot convert the current drive.
COPY Copies one or more files to another location.
DATE Displays or sets the date.
DEFRAG Disk defragmenter accessory.
DEL Deletes one or more files.
DIR Displays a list of files and subdirectories in a directory.
DISKCOMP Compares the contents of two floppy disks.
DISKCOPY Copies the contents of one floppy disk to another.
DISKPART Displays or configures Disk Partition properties.
DOSKEY Edits command lines, recalls Windows commands, and creates macros.
DRIVERQUERY Displays current device driver status and properties.
ECHO Displays messages, or turns command echoing on or off.
ENDLOCAL Ends localization of environment changes in a batch file.
ERASE Deletes one or more files.
EXIT Quits and closes the command shell.
EXPAND Expands one or more compressed files.
FC Compares two files or sets of files, and displays the differences between them.
FIND Searches for a text string in a file or files.
FINDSTR Searches for strings in files.
FOR Runs a specified command for each item in a set.
*FORFILES Selects files in a folder for batch processing.
FORMAT Formats a disk for use with Windows.
FSUTIL Displays or configures the file system properties.
FTYPE Displays or modifies file types used in file extension associations.
GOTO Directs the Windows command interpreter to a labeled line in a batch program.
GPRESULT Displays Group Policy information for machine or user.
GRAFTABL Enables Windows to display an extended character set in graphics mode.
HELP Provides Help information for Windows commands.
*ICACLS Display, modify, backup, or restore ACLs for files and directories (more here).
IF Performs conditional processing in batch programs.
LABEL Creates, changes, or deletes the volume label of a disk.
MD Creates a directory.
MKDIR Creates a directory.
*MKLINK Creates Symbolic Links and Hard Links
MODE Configures a system device.
MORE Displays output one screen at a time.
MOVE Moves one or more files from one directory to another directory.
OPENFILES Queries, displays, or disconnects open files or files opened by network users.
PATH Displays or sets a search path for executable files.
PAUSE Suspends processing of a batch file and displays a message.
POPD Restores the previous value of the current directory saved by PUSHD.
PRINT Prints a text file.
PROMPT Changes the Windows command prompt.
PUSHD Saves the current directory then changes it.
RD Removes a directory.
RECOVER Recovers readable information from a bad or defective disk.
REM Designates comments (remarks) in batch files
REN Renames a file or files.
RENAME Renames a file or files.
REPLACE Replaces files.
RMDIR Removes a directory.
ROBOCOPY Advanced utility to copy files and directory trees
SET Displays, sets, or removes environment variables for current session.
SETLOCAL Begins localization of environment changes in a batch file.
SETX Sets environment variables.
SC Displays or configures services (background processes).
SCHTASKS Schedules commands and programs to run on a computer.
SHIFT Shifts the position of replaceable parameters in batch files.
SHUTDOWN Allows proper local or remote shutdown of machine.
SORT Sorts input.
START Starts a separate window to run a specified program or command.
SUBST Associates a path with a drive letter.
SYSTEMINFO Displays machine specific properties and configuration.
*TAKEOWN Allows an administrator to take ownership of a file (more here).
TASKLIST Displays all currently running tasks including services.
TASKKILL Kill or stop a running process or application.
TIME Displays or sets the system time.
*TIMEOUT Pauses the command processor for the specified number of seconds.More here.
TITLE Sets the window title for a CMD.EXE session.
TREE Graphically displays the directory structure of a drive or path.
TYPE Displays the contents of a text file.
VER Displays the Windows version.
VERIFY Tells Windows whether to verify that your files are written correctly to a disk.
VOL Displays a disk volume label and serial number.
*VSSADMIN Volume Shadow Copy Service administration tool
*WHERE Displays the location of files that match a search pattern.
XCOPY Copies files and directory trees.
WMIC Displays WMI information inside interactive command shell
ATTRIB Displays or changes file attributes.
BREAK Sets or clears extended CTRL+C checking.
*BCDEDIT Sets properties in boot database to control boot loading.
CACLS Displays or modifies access control lists (ACLs) of files.
CALL Calls one batch program from another.
CD Displays the name of or changes the current directory.
CHCP Displays or sets the active code page number.
CHDIR Displays the name of or changes the current directory.
CHKDSK Checks a disk and displays a status report.
CHKNTFS Displays or modifies the checking of disk at boot time.
*CHOICE Batch file command that allows users to select from a set of options.
CIPHER Displays or alters the encryption of directories [files] on NTFS partitions.
*CLIP Redirects output of another command to the Windows clipboard.
CLS Clears the screen.
CMD Starts a new instance of the Windows command interpreter.
*CMDKEY Creates, lists and deletes stored user names and passwords or credentials.
COLOR Sets the default console foreground and background colors.
COMP Compares the contents of two files or sets of files.
COMPACT Displays or alters the compression of files on NTFS partitions.
CONVERT Converts FAT volumes to NTFS. You cannot convert the current drive.
COPY Copies one or more files to another location.
DATE Displays or sets the date.
DEFRAG Disk defragmenter accessory.
DEL Deletes one or more files.
DIR Displays a list of files and subdirectories in a directory.
DISKCOMP Compares the contents of two floppy disks.
DISKCOPY Copies the contents of one floppy disk to another.
DISKPART Displays or configures Disk Partition properties.
DOSKEY Edits command lines, recalls Windows commands, and creates macros.
DRIVERQUERY Displays current device driver status and properties.
ECHO Displays messages, or turns command echoing on or off.
ENDLOCAL Ends localization of environment changes in a batch file.
ERASE Deletes one or more files.
EXIT Quits and closes the command shell.
EXPAND Expands one or more compressed files.
FC Compares two files or sets of files, and displays the differences between them.
FIND Searches for a text string in a file or files.
FINDSTR Searches for strings in files.
FOR Runs a specified command for each item in a set.
*FORFILES Selects files in a folder for batch processing.
FORMAT Formats a disk for use with Windows.
FSUTIL Displays or configures the file system properties.
FTYPE Displays or modifies file types used in file extension associations.
GOTO Directs the Windows command interpreter to a labeled line in a batch program.
GPRESULT Displays Group Policy information for machine or user.
GRAFTABL Enables Windows to display an extended character set in graphics mode.
HELP Provides Help information for Windows commands.
*ICACLS Display, modify, backup, or restore ACLs for files and directories (more here).
IF Performs conditional processing in batch programs.
LABEL Creates, changes, or deletes the volume label of a disk.
MD Creates a directory.
MKDIR Creates a directory.
*MKLINK Creates Symbolic Links and Hard Links
MODE Configures a system device.
MORE Displays output one screen at a time.
MOVE Moves one or more files from one directory to another directory.
OPENFILES Queries, displays, or disconnects open files or files opened by network users.
PATH Displays or sets a search path for executable files.
PAUSE Suspends processing of a batch file and displays a message.
POPD Restores the previous value of the current directory saved by PUSHD.
PRINT Prints a text file.
PROMPT Changes the Windows command prompt.
PUSHD Saves the current directory then changes it.
RD Removes a directory.
RECOVER Recovers readable information from a bad or defective disk.
REM Designates comments (remarks) in batch files
REN Renames a file or files.
RENAME Renames a file or files.
REPLACE Replaces files.
RMDIR Removes a directory.
ROBOCOPY Advanced utility to copy files and directory trees
SET Displays, sets, or removes environment variables for current session.
SETLOCAL Begins localization of environment changes in a batch file.
SETX Sets environment variables.
SC Displays or configures services (background processes).
SCHTASKS Schedules commands and programs to run on a computer.
SHIFT Shifts the position of replaceable parameters in batch files.
SHUTDOWN Allows proper local or remote shutdown of machine.
SORT Sorts input.
START Starts a separate window to run a specified program or command.
SUBST Associates a path with a drive letter.
SYSTEMINFO Displays machine specific properties and configuration.
*TAKEOWN Allows an administrator to take ownership of a file (more here).
TASKLIST Displays all currently running tasks including services.
TASKKILL Kill or stop a running process or application.
TIME Displays or sets the system time.
*TIMEOUT Pauses the command processor for the specified number of seconds.More here.
TITLE Sets the window title for a CMD.EXE session.
TREE Graphically displays the directory structure of a drive or path.
TYPE Displays the contents of a text file.
VER Displays the Windows version.
VERIFY Tells Windows whether to verify that your files are written correctly to a disk.
VOL Displays a disk volume label and serial number.
*VSSADMIN Volume Shadow Copy Service administration tool
*WHERE Displays the location of files that match a search pattern.
XCOPY Copies files and directory trees.
WMIC Displays WMI information inside interactive command shell
Windows comes with several
command-line tools for file management. The features and applications of Assoc
and Ftype are discussed.
Before
discussing the file management tools, I would like to quickly review some of
the basic facts about how Windows manages files. (More details can be found at another
site.) A very basic property of a file is its file type. Each
file type has a set of specific actions that can be carried out with it or to
it. The software that is assigned to do these actions with or to a particular
file type is said to be "associated" with the file type. There may be
several actions and different software may be involved for each particular
action. This set of software constitutes the program associations for a
given file type. The extension of a file is a tag that tells the
computer what the file type is and what is to be done with the file when it is
opened or double-clicked or otherwise invoked one way or the other. Microsoft
also uses the word "associate" in connection with file extensions and
refers to an extension being associated with a particular file type. All of
this information is stored in the Registry and can be edited or changed in
several ways. I have discussed methods that use the graphical interface on another site . Here we look at using the
command line.
Manage file type and extension
associations with the "assoc" command
This tool is very useful for managing the relationship or
association between file extensions and file types. the syntax is assoc
[.ext[=[fileType]]]If the plain command "assoc" is entered, you will
get a list of what file types correspond to the extensions currently registered
on the system. The list can be quite long so it is best to redirect to a file
or to pipe to the "more" command so that one full screen at a time
can be viewed assoc > list.txt
or assoc | more If the only parameter
is a file extension (including the leading period), the file type for that
extension will be given. For example, to see what file type is associated with .txt
, enter assoc .txtSince the names used for the various file types may not
always be obvious, the above can be a useful type of command, In this case, the
output would normally be .txt=txtfile. . To delete the file type association
for the file name extension .xyz (use with care), enter assoc .xyz=Another
use is to associate a given extension with a certain file type. As an example,
to associate the extension .log with type txtfile, enter assoc
.log=txtfile Note that more than one extension can be associated with a file
type. For example, the file type "jpegfile" typically has both the
extensions .jpg and .jpeg associated with it. Also note that it
is possible to create your own file extensions and to associate them with a
filetype.
For a Microsoft reference on assoc go here or to the
Windows Help and Support Center. You can also enter.the commandassoc /?
Manage file type and program
associations with the "ftype" command
As previously mentioned, each file type has a set of
operations and corresponding software associated with it. In particular, all
active file types have an action named "Open" that is the default
action. This is the action that is invoked when you double-click a file with an
extension associated with the file type. There may also be other actions
(listed in the Context Menu) but ftype deals with "Open". The
"Open" action is defined by a string that includes the fully
qualified path to the executable file that is to carry out the action and any
parameters that must be passed to the executable. The syntax for ftype
is ftype [fileType[=[openCommandString]]]
Entering the bare command "ftype" will list all of
the current file types that have the open command strings defined and the
corresponding command string. It can be quite a long list so it is best to
redirect to a file or to pipe to the "more" command. Having the list
can be convenient as a record of what programs are being used to open various
files.
If a particular file type is specified, then the command
string for that file type will be displayed. Using the text file type as an
example, you would enter ftype txtfile This would produce the output txtfile=%SystemRoot%\system32\NOTEPAD.EXE
%1This shows that the executable file that opens text files is notepad.exe
located in the folder \Windows\system32\ (The environment variable %SystemRoot% is used
to indicate the Windows folder.) Note the presence of the placeholder %1. This
is necessary because the full command for the open action requires the name of
the file that is to be opened.and the placeholder stands for the file name.
This command is useful when you want to see what program opens a particular
file type.
If it were desired to change the openCommandString to
use Wordpad instead of Notepad, the command (on one of my computers) would be ftype
txtfile="G:\Program Files\Windows NT\Accessories\wordpad.exe"
"%1" (The path for Wordpad will vary from one computer to the next.
This example is for illustration only). Note the use of quotation marks to
enclose a path with spaces in it. While changing program associations may be
easier using the Windows Explorer Tools-Folder Options dialog (no typing
required), the command line method can also be useful, especially in batch
files.
Introduction
to the Command Prompt
DOS is dead, long live the command line
Windows
IP Configuration Tool (ipconfig)Before proceeding further, I wish to clear up a
common misconception that the command prompt in Windows XP is the same as DOS.
Even some experts who know better sometimes refer to the command prompt as a
“DOS window”. In fact, Microsoft itself isn't always careful about the
distinction. There are some superficial resemblances and some commands with the
same name but in fact the old 16-bit DOS is dead. All remnants of DOS are
totally gone from the Windows XP kernel (there is a DOS emulator for legacy
programs). Windows XP is a 32-bit protected memory system with a totally
different approach from the DOS/9X/Me family. The command line in XP has many
more capabilities and none of the 16-bit limitations like the restriction to
the DOS 8.3 file name format. The augmented capabilities make the command line
a powerful tool.
The command prompt window
The
command prompt is run from its own window by invoking the Windows XP command
interpreter that is provided by the file cmd.exe
located in the folder \Windows\System32\.
(The old DOS command interpreter is
command.com.) If you look in this folder you may also see several
files that look suspiciously like some of the old DOS files. They are, however,
different 32-bit versions with many new features. The command prompt window can
be opened by entering "cmd" (without quotes) into Start-Run or through Start-All Programs-Accessories.
A black and white window (the colors can be changed) containing the command
prompt will open. The window looks just like the old DOS window but don’t be
fooled, it isn’t. Note that it is possible to open several windows containing
command prompts, all running independently. It is even possible to run a
separate command prompt shell inside another command prompt window.
Internal and external commands
There are two kinds
of commands that can be run from the command prompt. There are the internal
commands that are built into the command interpreter like “del” and “dir”.
These commands can only be run from a command prompt (or by invoking the
command interpreter in some other way). They are listed in the table below.
There is also a large list of external commands that use an additional
executable file that can be run from either the command prompt or the Start-Run
line. Details of the various commands are available in several
places. In the Professional version of Windows XP there is a help file ntcmds.chm,
which has details of all the commands and their many switches. The help file
can be opened by entering (without the quotes) "hh ntcmds.chm" into Start-Run. It may or
may not be in the Home Edition, depending on what setup you have. However, in
both versions a list of many (but not all) of the commands available can be
obtained by entering "help" (without quotes) into a command prompt.
For more detail on a specific command, enter "help command-name" or
"command-name /?" For example to get information on the command xcopy,
enter "help xcopy" or "xcopy /?”. Microsoft keeps moving things,
but the last time I checked they had a command line reference at this
link. Some of the commonly used commands are discussed on this
page and in the list given here.
Table I. Internal
commands in the command shell
|
|||
assoc
|
dir
|
move
|
set
|
break
|
echo
|
path
|
setlocal
|
call
|
endlocal
|
pause
|
shift
|
cd
|
exit
|
popd
|
start
|
cls
|
for
|
prompt
|
time
|
color
|
ftype
|
pushd
|
title
|
copy
|
goto
|
rd
|
type
|
date
|
if
|
rem
|
verify
|
del
|
md
|
ren
|
volume
|
Some symbols that are used
In
addition to the commands, there are several symbols that are used. These modify
or combine the actions of commands. The table below gives a list.
Table II. Symbols
used with commands
|
||
Symbol
|
Function
|
Example
|
>
|
Sends output to a named file. If file does
not exist, it creates one. Overwrites existing file
|
command > somefile
|
>>
|
Appends output to contents of a named file
or creates a file if none exists
|
command >> somefile
|
<
|
Uses contents of a named file as input to
a command
|
command < somefile
|
¦
|
Sends ("pipes") the output of
command1 to the input of command2
|
command1 ¦ command2
|
&
|
Used to combine two commands. Executes
command1 and then command2
|
command1 & command2
|
&&
|
A conditional combination. Executes
command2 if
command1 completes successfully
|
command1 && command2
|
¦¦
|
Command2 executes only if command1 does not complete
successfully.
|
command1 ¦¦ command2
|
@
|
Used in batch files at the beginning of a
line to turn off the display of commands
|
@echo off
|
The most commonly
used symbols are the two redirection symbols ">" and
">>" and the so-called pipe, "¦" . (Just to make sure
there is no confusion, the "pipe" is the symbol above the back slash
on most keyboards. On keyboards it has a break in the middle but the break does
not always show when you type the symbol. A special code is used to show it on
a Web page.)
A frequent use of
the redirection is to save some output to a text file. For example the command
dir
somefolder > somefile.txt
sends a list
of the files in "somefolder" to a text file "somefile.txt".
More about this type of use is on this page. A common use of the
"pipe" is to control the screen display of some command with a lot of
output. For example, if you want to check the list of files in a folder with
many files, you can display one full screen at a time by piping to the command "more"
dir somefolder ¦ more
Command Line List and Reference
The complete list of possible
commands is quite large. Collected here is a selection of those that I believe
are likely to be the most applicable to home PC use.
Many of the commands listed below are also discussed in more
detail elsewhere on this site as is indicated by the link "details
here". Most commands have switches that are not given in the table. For
more information, open a command prompt and enter "commandname /?"
(without quotes). Detailed information about these commands and a larger list
is available at this Microsoft reference.
Selected
list of commands
|
||
Command
|
Description
|
Example
|
assoc
|
Displays or modifies file name
extension associations. Used alone, displays a list of all the current
file name associations
|
|
at
|
Schedules commands and programs to
run on a computer at a specified time and date. Requires the Schedule
service. Superseded by schtasks
|
|
attrib
|
Configures file attributes read
only, hidden, system
|
|
bootcfg
|
Used to repair or edit the boot.ini
file
|
|
cd or chdir
|
Displays the name of the current
directory or changes the current folder
|
cd folderpath
|
chkdsk
|
Checks hard drives for errors.
With switches,does repairs.
|
|
cls
|
Clears the screen
|
cls
|
copy
|
Copies a file from one location to
another
|
copy somefile somefolder
|
del
|
Deletes one or more files
|
|
dir
|
Displays a list of a folder's
files and subfolders
|
|
echo
|
Used to display a message or to
turn off/on messages in batch scripts
|
echo message
|
exit
|
Exits batch script or current
command control
|
exit
|
fc
|
Compares two files and displays
the differences between them
|
fc file1 file2
|
find
|
Searches for a text string in a
file or files. Can also be used with output from another command.
|
|
for
|
Runs a specified command for each
item in a set
|
|
fsutil
|
Displays and configures certain
file system properties. A suite of various commands
|
|
ftype
|
Displays or modifies file types
used in file name extension associations
|
|
getmac
|
Returns the media access control
(MAC) address for your network card
|
getmac
|
goto
|
Directs the Windows command
interpreter to a labeled line in a batch program
|
|
if
|
Performs conditional processing in
batch programs
|
|
ipconfig
|
Displays all current TCP/IP
network configuration values and refreshes Dynamic Host Configuration
Protocol (DHCP) and Domain Name System (DNS) settings
|
|
md or mkdir
|
Creates a directory (folder) or
subdirectory (subfolder)
|
|
more
|
Displays one screen of output at a
time. Used with another command that has extensive output
|
|
move
|
Moves a file from one folder to
another
|
|
net
|
A suite of various networking and
service commands
|
|
netsh
|
Network services shell . Complex
suite of commands.
|
|
netstat
|
Displays active TCP connections,
ports on which the computer is listening, Ethernet statistics, the IP routing
table, statistics for the IP, ICMP, TCP, and UDP protocols
|
|
path
|
Sets the command path in the PATH
environment variable, which is the set of directories used to search for
executable files
|
|
pathping
|
Provides information about network
performance and conditions at intermediate hops between a source and
destination
|
|
pause
|
Used in batch scripts
|
pause
|
ping
|
Checks connectivity to other networked
computers, routers, or Internet sites
|
|
popd, pushd
|
Changes the directory being
referenced in a command prompt. Pushd changes the directory and stores the
previous directory. Popd changes the current directory to the directory
stored by the pushd command
|
pushd somefolder
popd |
powercfg
|
Manages the power settings such as
hibernation. Has numerous switches
|
|
reg
|
Adds, changes, and displays
registry entries. A suite of various commands
|
|
rd or rmdir
|
Deletes a directory (folder)
|
|
ren or rename
|
Changes the name of a file or a
set of files
|
|
sc
|
Used to obtain information about
services and to configure them. A suite of various commands
|
|
schtasks
|
Schedules commands and programs to
run periodically or at a specific time
|
|
set
|
Displays, sets, or removes
environment variables
|
|
sfc
|
System file checker scans and
verifies the versions of all protected system files
|
sfc /scannow
|
shutdown
|
Shuts down or restarts a computer
|
|
sort
|
Alphabetizes strings from a text
file or the output of a command.
|
|
start
|
Starts an application or opens a
new command window
|
|
subst
|
Associates a folder with a drive
letter
|
|
systeminfo
|
Displays detailed configuration
information about a computer and its operating system
|
systeminfo | more
|
taskkill
|
Ends one or more tasks or
processes
|
|
tasklist
|
Displays a list of applications
and services with their Process ID (PID) for all tasks running
|
|
tree
|
Graphically displays the directory
structure of a folder or drive
|
tree somefolder
|
type
|
Displays the contents of a text
file
|
type somefile.txt
|
xcopy
|
Powerful command with many
switches for copying and backing up files and folders
|
Commands
that everybody can use
Since
the command prompt is often used by systems administrators, many of the
commands are specialized for networks and administration. However, the average
PC user is not left out; there are some powerful commands for everyday tasks
that anybody will find useful. Here we discuss some examples.
For convenience in
the examples below, I will use simple names for files and folders without
indicating the full path. Please remember that paths for all commands are
relative to the folder indicated in the command prompt itself, unless
explicitly indicated otherwise. The default reference folder is usually C:\Documents
and Settings\(log on name)\. Thus if a
reference is made to a file "somefile.txt", the computer assumes you
mean C:\Documents and Settings\(log on name)\somefile.txt.
If what you really want is C:\someotherfolder\somefile.txt,
then you must enter the entire name with the correct path. Note that paths
containing spaces have to be enclosed in quotes. A convenient way to be able to
open the command prompt in a folder of your choice can be obtained by
installing the Microsoft PowerToy “Command Prompt Here”. The right-click
context menu will then contain an entry for opening a command prompt in any
selected folder. The accessory can be downloaded here.
Another way to get file names into the command line without having to type a
long path is by using drag and drop. Open a command window and enter the
command you want with a space after it. Then use Windows Explorer to open the
folder containing the file you want to use. Drag the file over to the command
window and drop it. (Drag and drop does not work in Vista.)
Power deleting with the expanded "Del" command
The
delete command “del” now has a switch “/s” that provides for deletions in
subfolders. Thus the command
del /s myfolder\*
will delete all files in myfolder
and all files in any subfolders of myfolder.
Note the convenient asterisk wildcard “*”, which allows for multiple deletions
in a single user operation. Together with the switch “/s”, a single “del”
command can clean out Temp
folders and do other useful housekeeping chores. Another switch "/f"
will force the deletion of read-only files. If you are sure about what is being
deleted, add the “/q” switch to run in quiet mode so you aren’t asked if you
really want to delete for every single file.
Because of its power, this extended del command has to be used carefully. Any
files deleted this way do not go into the Recycle Bin but are permanently
removed.
To delete only files
with a particular extension EXT, use the command
del
/s myfolder\*.ext
Note that this
command will delete all files of a particular type in a folder and all its
subfolders. One example of its use is to get rid of all temporary files with
the extension TMP. Enhanced management of folders (directories)
The command
"rmdir" or its twin "rd" are also expanded compared to the
old DOS version. To remove folders (directories), use “rmdir” (just “rd”
will also work). Folders must be empty before they can be deleted. However,
there is a switch “/s” for deleting subfolders and with this switch files are
also deleted. It is like the old command "deltree". The command
rd
/s myfolder
will remove
"myfolder" and everything in it. Adding the switch /q for a
"quiet" mode is also possible.
Options have also
been added to the command for making folders. The command “mkdir” or “md” can
now make a whole tree. For example, consider the command
md
new\new1\new2
This will create a
folder “new” with a subfolder “new1” that in turn has a subfolder “new2”. Xcopy- Powerful and versatile way to copy or back up files
For copying large
numbers of files or backing up a large folder, the command line is often the
fastest and easiest way to go. The command “xcopy” is a very useful and
powerful command for this purpose. (The old DOS also had an “xcopy” command but
it sometimes had trouble with long file names. The XP version has no such
problems.) “xcopy” comes with an alphabet soup of assorted
switches that give it great versatility for use as a file backup
utility. Enter “xcopy /?” in a command prompt to see them all. For example with
the switch “/d:[mm-dd-yyy]” only files changed after a given date are copied. A
command that will copy all files from the folder myfolder that have changed since June 1,
2003 to the folder mybackup
is given by
xcopy myfolder mybackup /d:06-01-2003
If no date is specified the switch “/d” will copy all files that have changed
at any time.As is true in general, if there are spaces in a name, the path and
file name have to be enclosed in quotes. Adding the switch "/s"
provides that subfolders and their contents will also be copied. Other switches
provide for read-only and hidden files. Altogether, there are something like 27
command line options for xcopy.
More information is on this page.How to list files with "dir"
The "dir"
command is not new but it remains one of the most useful for average PC users.
If you have ever wanted to make a list of all the files contained in a
particular folder, you will have discovered that the Windows GUI provides no
easy way to do this. It is very straightforward, however, when using the
command line. The command “dir myfolder” will list the files and folders
contained in myfolder.
Again, there are switches that provide for various modifications of the
command. For example “/h” will show hidden files and “/s” will list the
contents of sub-folders in addition to those of the main folder. Of course, the
normal output of the command is to the screen. To output to a file instead of
the screen, the command is
dir myfolder
>listmyfolder.txt
where “>” is the
redirection symbol. The file "listmyfolder.txt" will be created by
the command. Output can also be redirected straight to a printer on the LPT1
port but I think it is better to first create a file and then print from there
if hardcopy is desired. These lists can be a lot longer than you might think.
(These days most printers are on USB, anyway.) This use of dir is also available in
Windows 98/Me.
The dir command can also be
used to list only files with a given extension. For example
dir
myfolder\*.doc /s >listmyfolder.txt
will list all Microsoft Word files in myfolder
and its subfolders. This form of the command will also list all the directories
and sub-directories. If you want a list of filenames only, add the switch /b. The filename will
include the full path. Renaming files with "ren"
Renaming a a large
number of files can be tedious. The command ren
(also written rename)
is somewhat limited but its ability to use wild cards can sometimes be useful.
The basic command is
ren file1 file2
The renamed file has to stay in the same folder as the original; this command
cannot move files to another folder. The wildcard capability can be used to
change the extension of all files of a certain type. Thus ren
*.txt *.doc
will rename all text
files to have a DOC extension.Moving files
The command
"move" takes a file from one folder and puts it in another. Its ability
to use wild cards makes it useful for moving all the files of a given type to
another location. A command of the type
move
/y folder1\*.mp3 folder2\
will move all
MP3 files from folder1
to folder2. The
switch " /y" is used if you want to prevent the system from asking if
it should overwrite existing files of the same name. To prevent overwriting,
use the switch "/-y". Changing file attributes with "attrib"
In
addition to their actual content, files also have a set of properties that
characterize them (sometimes called metadata.) One set of these properties are
the four attributes read-only,
hidden, system, and archive.
The archive attribute is primarily used in backup procedures but the other
three can be encountered in various contexts. These attributes can be turned on
or off with the command "attrib" and its switches. The great utility
of this command is that it can act on subfolders with its switch "/s"
and can use the wildcard "*". For example, to clear the read-only ,
system, and hidden attributes from a file use
attrib -r -s -h somefile
This operation is not uncommon when system files have to be edited. To restore
the attributes the command is attrib +r +s +h somefile
A common situation where it is desirable to clear the read-only attribute from
many files is when files are copied from a CD. By default CD files are normally
marked read-only. This can interfere with editing. To clear the read-only
attribute from all files in a folder and its subfolders use attrib -r
somefolder\*.* /s
If you want to process all files of a certain
type such as MP3, use attrib -r somefolder\*.mp3 /s
How to make your favorite folder easily accessible in Windows dialog boxes
Another older command
that I find handy is "subst". There are certain folders that I use
over and over and I like to have ready access to them. One way to do this is to
use the command “subst” to assign a drive letter to a folder. Since drives are
at the top of My Computer
and any folder trees in browse lists, it makes the folder very easy to get to.
To map the “Z:” drive to a folder "myfolder", enter
subst
z: myfolder
Unless you are working from the
parent folder of "myfolder" you will need the full path for
it. The assignment only lasts until the user logs off or the computer is shut
down so I have a one-line batch file in my Startup folder that reinstitutes the
assignment.Other commands
There are so many
commands that we can only give the briefest sketches here. A list of some that
I think might be useful on home computers is given
here. I urge you to look into as many as possible since I feel you
will be surprised at how useful some can be. For example, there are a whole
host of commands for checking network functions and for use on the Internet.
(Many have names that begin with “net…”) There are new ones as well
as versions of the well-known commands such as “ping” and “tracert”. As more
and more people have home networks, these commands are assuming greater
significance to the average PC user. Go to this
page for more discussion of some networking commands.
Useful command line programs in scripts
Average PC users are
not always comfortable using the command line and I have used VBScripts to wrap
some of the examples discussed above with an easy-to-use graphical interface.
Description of the free scripts and instructions for their use and downloading
are at a sister site.
Configuring
the Command Prompt Window
The
interface to the command shell can be customized in a number of ways and these
are discussed.
The
default settings for the window that displays a command prompt can be changed
to suit individual preferences. Among the properties that can be changed are
those that affect the appearance such as window size, background and foreground
color, and font style. Others that affect operation such as the editing mode
and command history buffer can also be configured.
The command prompt properties dialog
Changing the
settings for the command prompt can be done through the properties dialog box.
This can be reached in the menu that is opened by left-clicking the icon in the
left-top corner or by right-clicking anywhere in the title bar at the top of a
command prompt window. In the menu that opens choose "Properties".
Figures 1 and 2 show the procedure.
Options tab
The figure on the
right shows the dialog box for the Options tab. Settings here include provision
for configuring cursor size and window or full-screen display. The "Quick
Edit" mode allows you to use the mouse to cut and paste text to and from
the command window. You can also choose insert or overwriting for editing by
checking or unchecking "Insert Mode".
Command History buffer
A new feature is the
"Command History" buffer. This buffer stores the previous commands
that you have entered so that you do not have to retype them (reminiscent of
Doskey). The default value is 50 but can be made as large as 999 (remember that
they do take RAM) . The up-and-down arrow keys can be used to navigate the
previously entered commands. Alternatively, pressing the F7 key will display a
pop-up window with a list of the commands.
Font tab
This
tab is more or less self-explanatory. On most machines, there is a choice of
two font faces, Raster (the default) and Lucinda Console. Lucinda Console is
more versatile. A selection of font sizes is available. As is true in general
about settings, changes in font can be made for the present window only or for
all command windows with the same title.
Layout tab
The
window size and position can be set here. There are also settings for the
screen buffer size. This determines how many lines back that you can scroll.(
Incidentally, this ability to scroll back to previous commands was not present
in DOS. Once something was off the screen, you couldn't scroll back.)
Color tab
The dialog box for
configuring colors is shown on the right. The default colors for a command
window and its fonts are the old black and white combination. However, other
color combinations are available. The colors for pop-up windows associated with
the command window can also be configured. As shown in the figure on the right,
colors can be changed by clicking on the appropriate choice or by entering
numerical values in the 256 color RGB notation. In the figure, I have chosen a
blue screen background with yellow screen text as illustration. Color changes
can be made for the current screen only or applied to all command windows.
Screen colors can
also be changed with the "color" command or a command-line switch
directly modifying the command interpreter. Both these methods are discussed
below.
It is also possible
to have shortcuts that open the command line with more than one color scheme
and this is discussed in the shortcut section below.
Applying changes to all command windows
Note that changes
apply to the current command window only unless you specify otherwise. When
making configuration changes, you will be shown the dialog box on the right. To
make changes stick after the current command session is closed, check the
button by the entry, " Save properties for future windows with same
title".
Configuring shortcuts for the command prompt
If you use the
command prompt a great deal, you may want to place a shortcut on the desktop or
in the Quick Launch bar. After creating the shortcut, you can configure the
properties of the command window that it will open in much the same way as
discussed above. Right-click the shortcut and choose "Properties"
from the context menu. Four of the the tabs at the top of the properties sheet
will be the same as those discussed above. They are marked in the figure on the
right. You can apply whatever customization you like and it will apply only to
command windows that are opened from this particular shortcut.
Another
way to configure the properties of a particular shortcut is to apply the
changes in a command window that has been opened with that shortcut. After
configuring the changes to the open command window by the methods discussed in
sections above, the dialog box shown on the right will open. Check the button
by the entry, "Modify shortcut that started this window".
The "color" command
The screen colors
can be configured from the command line itself with the command
"color" followed by a two-digit hexadecimal number. The first digit
determines the background and the second determines the text color. The table
below shows the relationship between the hex numbers and colors.
Table I.
Hexadecimal color codes
|
|
0 = Black
|
8 = Gray
|
1 = Blue
|
9 = Light Blue
|
2 = Green
|
A = Light Green
|
3 = Aqua
|
B = Light Aqua
|
4 = Red
|
C = Light Red
|
5 = Purple
|
D = Light Purple
|
6 = Yellow
|
E = Light Yellow
|
7 = White
|
F = Bright White
|
For example the
command "color
1E" will give a blue background with yellow text. Settings made
this way apply only to the current session. Entering "color" with no
argument will return the system to the starting colors.
Switches for the command interpreter cmd.exe
Another way to
modify the behavior of the command prompt is to use switches with the command
interpreter cmd.exe.
The syntax for cmd.exe
is:
cmd [[{/c|/k}] [/s] [/q] [/d] [{/a|/u}] [/t:fg] [/e:{on|off}] [/f:{on|off}] [/v:{on|off}] string]
Table II describes the parameters briefly. See the Windows Help and Support Center for more detail.
cmd [[{/c|/k}] [/s] [/q] [/d] [{/a|/u}] [/t:fg] [/e:{on|off}] [/f:{on|off}] [/v:{on|off}] string]
Table II describes the parameters briefly. See the Windows Help and Support Center for more detail.
Table II. Switches
for cmd.exe
|
|
Parameter
|
Description
|
/c
|
Carries out the command specified by string
and then exits
|
/k
|
Carries out the command specified by string
and stays open
|
/s
|
Modifies the treatment of string
after/c
or /k.
See Windows Help for details
|
/q
|
Turns the echo off. Default is echo on
|
/d
|
Disables execution of AutoRun commands
|
/a
|
Creates ANSI output (the default)
|
/u
|
Creates Unicode output
|
/t:fg
|
Sets the foreground f and
background g colors. The hex codes for f and g
are in Table I.
|
/e:on /e:off
|
Enables or disables commands extensions.
The default is "on"
|
/f:on /f:off
|
Enables or disables file and directory
name completion
|
/v:on /v:off
|
Enables or disables delayed environment
variable expansion
|
string
|
Specifies the command you want to carry
out
|
Doskey in the Windows XP Command Shell
The Windows XP command console
contains an accessory named after the old command-line utility called Doskey.
Its functions are discussed.
As the name
implies, Doskey was part of the old DOS command shell. It provided command-line
editing, history functions for recalling commands, and a way to write macros, A
similarly-named tool is still present in the 32-bit command shell provided by cmd.exe
but its functions have been largely superseded. For example, if extensions
are enabled (the default setting), a buffer that stores command- line entries provides for the easy recall of up to 50 previously entered
commands without need for Doskey. Using the Up and Down arrow keys will
navigate among previously entered commands. Unless you are working for long
periods of time within the command console, I also see little advantage of
macros over batch files. I include this page for completeness but I have not
personally used Doskey for years.
Syntax and functions
The figure
below summarizes the syntax for Doskey and its switches and functions.
File
System Utility- Fsutil.exe
The
file system utility "fsutil" is a suite of command-line operations
for displaying and managing certain file and drive properties. Some
applications are described.
Fsutil
is an advanced tool intended primarily for system administrators but more
experienced PC users will also find that it has a number of possible
applications. Some that I think may be of interest are discussed. The tool is
present in both Windows XP and Vista and is primarily of use for NTFS systems.
It requires administrative privileges.
Subcommands
Fsutil
contains a suite of subcommands, which are listed in Table I. Each of these
subcommands may in turn have additional subcommands of its own. Many of these
are quite specialized but some that are of more general interest are discussed
in sections further on. Windows Vista has two additional subcommands not
present in Windows XP and these are indicated in the table. They are included
for completeness but are of limited interest to most PC users.
Table I.
Subcommands for Fsutil
|
|
Subcommand
|
Description
|
behavior
|
Manages
the settings for generating 8.3 character-length file names and for, updating
the last access timestamp. Manages the amount of disk space reserved for the
Master File Table.
|
dirty
|
Queries or sets a volume's dirty bit.
|
file
|
Finds a file by its security identifier,
queries allocated ranges for a file, sets a file's short name, sets a file's
valid data length, or sets zero data for a file.
|
fsinfo
|
Lists all drives, queries the drive type,
queries volume information, queries NTFS-specific volume information, or
queries file system statistics.
|
hardlink
|
Creates a hard link
|
objectid
|
Manages object identifiers
|
quota
|
Manages disk quotas on NTFS volumes
|
repair (Vista)
|
Self healing management
|
reparsepoint
|
Queries or deletes reparse points
|
sparse
|
Manages sparse files
|
transaction (Vista)
|
Transaction management
|
usn
|
Manages the update sequence number (USN)
change journal
|
volume
|
Dismounts
a volume or queries to see how much free space is available on a disk.
|
Examples of applications of Fsutil
Here is a selection
of applications of Fsutil
that I have seen mentioned most often on the Web. If I have omitted one of your
favorites, let me know and I will add it to the list.
Applications of the subcommand "behavior"
The subcommand
"behavior" may be the one that an ordinary PC user is most likely to
encounter. There are several features of the NTFS system that can be configured
to possibly speed up the system and tweaks involving this subcommand are fairly
commonly mentioned on the Web and in books. The subcommand "behavior"
has two further subcommands. They are "query", which displays the
current values for option settings and "set", which is used to change
settings. The options that are available are shown in Table II. Options that
are available only in Vista are indicated. Commands have the form
fsutil
behavior query {option} {value}
and fsutil behavior set {option} {value}
Commands
involving "set" can change Registry entries and may require a reboot
to take effect.
Table II. Options
for "fsutil behavior"
|
|
Option
|
Possible Values
|
allowextchar
|
0 or 1
|
disable8dot3
|
0 or 1
|
disablecompression (Vista)
|
0 or 1
|
disablelastaccess
|
0 or 1
|
disableencryption (Vista)
|
0 or 1
|
encryptpagingfile (Vista)
|
0 or 1
|
mftzone
|
0 through 4
|
memoryusage (Vista)
|
0, 1 , 2
|
quotanotify
|
1 through 4294967295 seconds
|
SymlinkEvaluation (Vista)
|
Various
|
Find the current settings
To display the
current settings on a system, use a command with "query" such as:
fsutil
behavior query disablelastaccess
Disable short file names to speed up Windows
One tweak that is
mentioned fairly often disables the creation of short 8,3 format file names. By
default both Windows XP (NTFS) and Vista create file names in the old 8.3
format for all files in addition to whatever the regular name is. This is to
ensure compatibility with some programs that still linger and require the old
file naming format from DOS days. If you are sure that you do not have any
16-bit programs or programs that require the old format, disabling this extra
name creation can possibly speed up your system.The command is:
fsutil
behavior set disable8dot3 1
Note that
the Windows XP environment variables %TEMP% and %TMP%
typically use short names. Program installations sometimes use these variables
If this change causes trouble and you need to restore the short name function,
the command is fsutil behavior
set disable8dot3 0
Disable timestamp for last access to a file to speed up Windows
Another frequently
seen recommendation is to disable the setting that keeps track of the last time
a file. was accessed. Removing the necessity for the system to keep reading and
writing this information may speed up Windows Explorer. The command is:
fsutil
behavior set disablelastaccess 1
Note that some backup programs may need this information. If you wish to
restore the timestamp, the command is: fsutil
behavior set disablelastaccess 0
Disable Encrypting File System in Windows Vista
Windows Vista Business
and Ultimate come with a feature called the Encrypting File System
(EFS). This can be fairly demanding of resources and if you have a marginal
system that does not require this security feature, you can turn EFS off. The
command is
fsutil behavior set disableencryption 1
To
restore EFS, use the commandfsutil behavior
set disableencryption 0
(Although Windows XP
Professional has EFS, this particular command is not available.).Change the size of the Master File Table
NTFS uses a Master
File Table (MFT) to store information about folders and files. Entire small
files may even be included. By default, 12.5% of the volume is allocated to the
MFT. Unless you have a small volume or a very large number of files, the
default allocation should suffice. However, if you need more space for the MFT,
you can use the command
fsutil behavior
set mftzone
n
The parameter "n" can be 0 to 4. Table III shows the MFT allocation
corresponding to each value of "n".
Table III. MFT
space allocations
|
|
value for n
|
Space allocation
for MFT
|
0
|
No setting. Uses the default of 12.5%
|
1
|
12.5%
|
2
|
25%
|
3
|
37.5%
|
4
|
50%
|
Displaying some drive properties
Fsutil
has some very advanced methods for managing hard drives but I will mention only
a few of more general interest.
Obtaining drive lists for a computer
There are other ways
of doing this but you can obtain a list drives by letter type by using the
command:
fsutil fsinfo drives
Obtaining drive type
You can the drive
type for a given drive with the command:
fsutil
fsinfo drivetype D:
The command will
return "Fixed drive", "CD-ROM drive", or "Removable
drive".Obtaining some general volume information
You can obtain a list
of various volume parameters with:
fsutil
fsinfo volumeinfo C:
Determining amount of free space on a drive
To determine the
amount of free space on a drive, use the command
fsutil
volume diskfree C:
Net Services Commands in Windows XP
A large family of commands beginning
with the initial string "net" are available in Windows XP
Professional. They are listed here.
The Net Services suite of commands is described in the Windows
Help and Support Center. Enter "net services" to obtain a list of
the services and their syntax for usage.You can also see a list of all
available net commands by typing "net /?" at a command prompt. Syntax
help is obtained by typing "net help {command}". For example,
for help with the "net stop" command, type net help stop
The list of commands and a brief description of each is given
below. Some of these commands duplicate functions available in other ways, such
as in the Netsh suite or the Service
Controller.
·
Net accounts - Updates the user accounts database
and modifies password and logon requirements for all accounts.
·
Net computer - Adds or deletes computers from a
domain database
·
Net config - displays a list of configurable
services
·
Net continue - Continues a service that has been
suspended by net pause
·
Net file - Displays the names of all open
shared files on a server
·
Net group - Adds, displays, or modifies global
groups in domains
·
Net help - Provides a list of network
commands and topics for which you can get help
·
Net helpmsg - Explains why an error occurred and
provides problem-solving information
·
Net localgroup- Adds, displays, or modifies local
groups
·
Net name - Adds or deletes a messaging name
·
Net pause - Pauses services that are currently
running.
·
Net print - Displays information about a
specified print queue, displays information about all print queues hosted by a
specified print server, displays information about a specified print job, or
controls a specified print job.
·
Net send- Sends a messenger service message
·
Net session- Lists or disconnects sessions
·
Net share- Displays or manages shared
printers or directories
·
Net start- Lists or starts network services
·
Net statistics- Displays workstation and server
statistics
·
Net stop- Stops services
·
Net time- Displays or synchronizes network
time
·
Net use- Displays or manages remote
connections
·
Net user- Creates local user accounts
·
Net view- Displays network resources or
computers
Net User command in Windows Vista
User accounts play a large role in Vista and the "net
user" gives a method for managing them. Although user accounts can be
managed in several ways through the normal graphical interface, the command
line can be quicker and can be scripted.
Netstat
Netstat
is a useful tool for checking network and Internet connections. Some useful
applications for the average PC user are considered, including checking for
malware connections.
Syntax and switches
The command syntax
is
netstat [-a] [-b] [-e] [-n] [-o] [-p proto] [-r] [-s] [-v]
[interval]
A brief description of the
switches is given in Table I below.
Note that switches for Netstat use the dash symbol "-" rather than
the slash "/".
Table I. Switches
for Netstat command
|
|
Switch
|
Description
|
-a
|
Displays all connections and listening
ports
|
-b
|
Displays the executable involved in
creating each connection or listening port. (Added in XP SP2.)
|
-e
|
Displays Ethernet statistics
|
-n
|
Displays addresses and port numbers in
numerical form
|
-o
|
Displays the owning process ID associated
with each connection
|
-p proto
|
Shows connections for the protocol
specified by proto; proto may be any of: TCP, UDP, TCPv6, or UDPv6.
|
-r
|
Displays the routing table
|
-s
|
Displays per-protocol statistics
|
-v
|
When used in conjunction with -b, will
display sequence of components involved in creating the connection or
listening port for all executables
|
[interval]
|
An integer used to display results
multiple times with specified number of seconds between displays. Continues
until stopped by command ctrl+c.
Default setting is to display once,
|
Applications of Netstat
Netstat is one of a
number of command-line tools available to check the functioning of a network. (See
this page for discussion of other tools.) It provides a way to check
if various aspects of TCP/IP are working and what connections are present. In
Windows XP SP2, a new switch "-B" was added that allows the actual
executable file that has opened a connection to be displayed. This newer
capability provides a chance to catch malware that may be phoning home or using
your computer in unwanted ways on the Internet. There are various ways that a
system administrator might use the assortment of switches but I will give two
examples that might be useful to home PC users.
Checking TCP/IP connections
TCP
and UDP connections and their IP and port addresses can be seen by entering a
command combining two switches:
netstat -an
An
example of the output that is obtained is shown in Figure 1.
Figure 1. Example
output for command "netstat -an"
|
The information that
is displayed includes the protocol, the local address, the remote (foreign)
address, and the connection state. Note that the various IP addresses include
port information as well. An explanation of the different connection states is given
in Table II>
Table II.
Description of various connection states
|
|
State
|
Description
|
CLOSED
|
Indicates that the server has received an
ACK signal from the client and the connection is closed
|
CLOSE_WAIT
|
Indicates that the server has received the
first FIN signal from the client and the connection is in the process of
being closed
|
ESTABLISHED
|
Indicates that the server received the SYN
signal from the client and the session is established
|
FIN_WAIT_1
|
Indicates that the connection is still
active but not currently being used
|
FIN_WAIT_2
|
Indicates that the client just received
acknowledgment of the first FIN signal from the server
|
LAST_ACK
|
Indicates that the server is in the
process of sending its own FIN signal
|
LISTENING
|
Indicates that the server is ready to
accept a connection
|
SYN_RECEIVED
|
Indicates that the server just received a
SYN signal from the client
|
SYN_SEND
|
Indicates that this particular connection
is open and active
|
TIME_WAIT
|
Indicates that the client recognizes the
connection as still active but not currently being used
|
Checking for malware by looking at which programs initiate connections
To find out which
programs are making connections with the outside world, we can use the command
netstat
-b
Actually, it is better to check over a period of time and we
can add a number that sets the command to run at fixed intervals. Also, it is
best to create a written record of the connections that are made over some
period of time. The command can then be written netstat
-b 5 >> C:\connections.txt
Note that as written, this command will run with five-second intervals until
stopped by entering "Ctrl+c",
which is a general command to exit. (Some reports say that this can be fairly
CPU intensive so it may cause a slower, single-core machine to run sluggishly.
It was not noticeable on my dual-core machine.) A simple example of the type of
output is shown in Figure 2. Note that the Process ID (PID) is given. This
command can be combined with other tools such as Task Manager to analyze what executable
files and processes are active and are trying to make Internet connections.
Figure 2. Sample
output for command "netstat -b"
|
Batch program to check connections and terminate automatically
The previous example
of using "netstat -b" to check connections at intervals has the
disadvantage that it requires manual termination. It is also possible to use a
batch file that runs a specified number of times with a given time interval and
then terminates automatically. In Windows XP we can make use of a command from
the Windows 2003 Server Tools called
"Sleep". A possible batch file is:
@echo
off
for /L %%X in (1,1,100) do (netstat -b >>
C:\connections.txt)&(sleep 5)
This
particular example does 100 iterations of the
netstat command at 5 second intervals.
Net Services Commands in Windows XP
A large family of commands beginning
with the initial string "net" are available in Windows XP
Professional. They are listed here.
The Net Services suite of commands is described in the Windows
Help and Support Center. Enter "net services" to obtain a list of
the services and their syntax for usage.You can also see a list of all
available net commands by typing "net /?" at a command prompt. Syntax
help is obtained by typing "net help {command}". For example,
for help with the "net stop" command, type net help stop
The list of commands and a brief description of each is given
below. Some of these commands duplicate functions available in other ways, such
as in the Netsh suite or the Service
Controller.
·
Net accounts - Updates the user accounts database
and modifies password and logon requirements for all accounts.
·
Net computer - Adds or deletes computers from a
domain database
·
Net config - displays a list of configurable
services
·
Net continue - Continues a service that has been
suspended by net pause
·
Net file - Displays the names of all open
shared files on a server
·
Net group - Adds, displays, or modifies global
groups in domains
·
Net help - Provides a list of network
commands and topics for which you can get help
·
Net helpmsg - Explains why an error occurred and
provides problem-solving information
·
Net localgroup- Adds, displays, or modifies local
groups
·
Net name - Adds or deletes a messaging name
·
Net pause - Pauses services that are currently
running.
·
Net print - Displays information about a
specified print queue, displays information about all print queues hosted by a
specified print server, displays information about a specified print job, or
controls a specified print job.
·
Net send- Sends a messenger service message
·
Net session- Lists or disconnects sessions
·
Net share- Displays or manages shared
printers or directories
·
Net start- Lists or starts network services
·
Net statistics- Displays workstation and server
statistics
·
Net stop- Stops services
·
Net time- Displays or synchronizes network
time
·
Net use- Displays or manages remote
connections
·
Net user- Creates local user accounts
·
Net view- Displays network resources or
computers
Net User command in Windows Vista
User accounts play a large role in Vista and the "net
user" gives a method for managing them. Although user accounts can be
managed in several ways through the normal graphical interface, the command
line can be quicker and can be scripted.
Netsh,
the Network Services Shell
A
suite of command line networking tools called Netsh that comes with its own
shell or interface is contained in a number of Windows operating systems and is
discussed here.
Introduction to Netsh
As more and more
home users set up networks, they are finding themselves to be de
facto system administrators. Home networks are very nice but they
require a certain amount of care and feeding. Fortunately, Windows XP comes
with a large assortment of command-line tools that can help maintain your
network. Although many are specialized and of interest only to administrators
of large corporate setups, some tools can be quite helpful to the home user as
well.
Many may find that
the basic tools like ping,
ipconfig, and netstat,
which are discussed on another page, are all that they care to
deal with but the more adventurous can take advantage of a complete suite of
powerful tools called Netsh.
This suite is invoked from the standard command-line but has it has own
interface or shell with a large number of sub-commands. I will try to focus on
the features of Netsh that I think can be helpful to the home user. The whole
suite has many applications and those who want more details can go to this Microsoft reference.
The Network Services
shell is opened by entering netsh
into a regular command prompt. The shell has a hierarchical structure with some
sub-shells that Microsoft calls "contexts". From the user's point of
view, however, all that this means is that commands are entered as a sequence
of terms. The following sections discuss the "contexts" of most use
to the home user.
The "netsh diag" context
The diagnostic
context "diag" contains useful tools for checking out a network and
testing various components and functions. Table I shows the contexts and
sub-commands of most interest to this discussion. A complete list and many
details are given at this Microsoft reference.
Table I. Some
sub-shells (contexts) and commands for Netsh diag
|
||
Context
|
Sub-context
|
Commands
|
diag
|
connect- Establishes,
verifies, and then drops a connection
|
iphost, mail, news
|
ping- Verifies
connectivity
|
adapter, iphost, mail, news
|
|
show- Lists network
components and settings
|
all, client, ip, mail, modem
|
|
gui- Starts the
network diagnostics tool in Help and Support Center.
|
Graphical user interface
|
This group of
commands provides ways to test some of the most common functions of interest to
home users. For example, you can test if your email server is working or check
your email settings by the command
netsh
diag connect mail
(Note that this may
not work for email clients like AOL.). Another example is to list important
settings withnetsh diag show
all
The graphical user interface
One way to simplify
diagnostic tasks is to use the Help Center interface that can be invoked by
entering
netsh diag gui
With this interface, you can carry out a number of diagnostic tests with one
operation. Figure 1 shows the available functions.
Figure 1. Settings
for GUI function of Netsh diag
|
The "netsh interface ip" context
This context is
another with functions that might interest a home user. It provides a way to
add, delete, modify, and display various IP addresses and TCP/IP settings.
Table II lists several functions. More detail and additional functions are
discussed in this Microsoft reference.
An example of its use is to display TCP/IP settings with the command
netsh
interface ip show config
This can also be
written netsh int ip show config
Table II. Some
commands for "netsh interface ip"
|
||
Context
|
Sub-context
|
Function
|
interface ip
or int ip |
set address
|
Configures an IP address and a default
gateway on a specified interface
|
show address
|
Displays address for specified interface
|
Reset Internet Protocol (TCP/IP)
Another example of
using the Netsh Internet Ip
context is resetting TCP/IP. For several reasons, including infestation from
spyware, these settings might get corrupted. Netsh
contains a command that will reset the TCP/IP stack to the original settings
that existed when the operating system was installed. These settings may not be
the most up-to-date for your system but they will allow you to reconfigure
after a spyware invasion or other problem. The command to reset TCP/IP is
netsh
int ip reset
{logfile}
Note that you must include the name of a file where a log of the actions will
be placed. Thus, if the log file is C:\tcplog.txt,
the command is netsh int ip
reset C:\tcplog.txt
A detailed
description of reinstalling TCP/IP is given at this Microsoft reference. Also, see the Winsock
section below. The "netsh winsock" context
Service pack 2 for
Windows XP includes some additions to the Netsh suite. These are discussed here and
include a new tool for repairing the Windows network socket or
"winsock". Uninstalling spyware or poorly written applications can
corrupt the winsock settings and result in loss of network connectivity. There
are two commands for managing the settings. To display a list of various
installed services (LSP, BSP, NSP) use
netsh
winsock show catalog
This list may not
be too meaningful for the average PC user but it can be helpful for more
experienced users. To reset the winsock to the default configuration use netsh
winsock reset catalog
Note that any
installed software that uses Internet connections may be partially disabled by
this action and have to be reinstalled. This would include most software that
updates itself and anti-virus programs that use proxy servers. Therefore, this
command should only be used for cases where the degree of corruption makes it
necessary. See this reference for some alternative
methods. Netsh Firewall Helper in Windows XP SP2
Microsoft changed
the way the firewall in Windows XP works when it issued service pack 2. It also
added capability to Netsh for extensive configuring of the firewall with a new
context "netsh firewall" that Microsoft calls the Firewall Helper.
Its use in troubleshooting firewall problems in SP2 is extensively discussed in this knowledge base article. With the
Firewall Helper Microsoft says you can now
•
Configure the default state of Windows Firewall. (Options include Off, On, and
On with no exceptions.)
• Configure the ports that must be open.
• Configure the ports to enable global access or to restrict access to the local subnet.
• Set ports to be open on all interfaces or only on a specific interface.
• Configure the logging options.
• Configure the Internet Control Message Protocol (ICMP) handling options.
• Add or remove programs from the exceptions list
• Configure the ports that must be open.
• Configure the ports to enable global access or to restrict access to the local subnet.
• Set ports to be open on all interfaces or only on a specific interface.
• Configure the logging options.
• Configure the Internet Control Message Protocol (ICMP) handling options.
• Add or remove programs from the exceptions list
The number of
possible commands is quite large but two main sub-contexts are
netsh
firewall set
and netsh
firewall show
An extensive list
of commands is in the knowledge base article
previously mentioned.
PowerShell
in Windows XP, Windows Vista, and Windows 7
Microsoft
has introduced a entirely new command line interface called
"PowerShell". Some of the new features are described.
Introduction to PowerShell
Microsoft
has developed a new command line interface (first called "Monad") and
renamed "PowerShell". It was first made available as a stand-alone
application for Windows XP (download here). and then for Vista ( available at this site).
It is now a standard part of Windows 7. The older command interpreter cmd.exe is still present
as well. The new shell is Microsoft's answer to Unix shell scripting. It is
quite different from the previous command line interface and is considerably
more powerful. It makes use of more sophisticated techniques and objects and requires the .NET Framework
2.0. It has new functions for systems and network administration and is aimed
at IT professionals. Because the purpose of this present site is to introduce
the command line to home PC users , PowerShell is somewhat beyond the intended
scope (and my personal experience). Nonetheless, I believe the home user should
be aware of PowerShell's potential and the more experienced may wish to explore
it further. I will try to outline very briefly what PowerShell is about.
PowerShell features
In
the previous Windows command line described elsewhere on this site, commands
consist of internal command strings that are interpreted and executed by the
command interpreter or of commands that invoke separate executable files.
PowerShell has a new approach that makes use of what Microsoft calls
"cmdlets". Here is Microsoft's description:
A
cmdlet (pronounced "command-let") is a single-feature command that
manipulates objects in Windows PowerShell. You can recognize cmdlets by their
name format -- a verb and noun separated by a dash (-), such as Get-Help,
Get-Process, and Start-Service.
Although each cmdlet
has a single function, groups of cmdlets can be strung together to carry out a
complex task. Also the output of many cmdlets can be used as input (piped) to
other cmdlets without additional processing. These capabilities represent a
significant advance over the present command line shell.
PowerShell continues
to recognize the commands from the older command shell although, in many cases,
the command is an alias for a PowerShell cmdlet
List of cmdlets
At
this time, PowerShell comes with 129 cmdlets. Since cmdlets are easily written,
more can be expected. Table I shows the list of those presently available.
Table I. List of
PowerShell cmdlets
|
|||
Add-Content
Add-History Add-Member Add-PSSnapin Clear-Content Clear-Item Clear-ItemProperty Clear-Variable Compare-Object ConvertFrom-SecureString Convert-Path ConvertTo-Html ConvertTo-SecureString Copy-Item Copy-ItemProperty Export-Alias Export-Clixml Export-Console Export-Csv ForEach-Object Format-Custom Format-List Format-Table Format-Wide Get-Acl Get-Alias Get-AuthenticodeSignature Get-ChildItem Get-Command Get-Content Get-Credential Get-Culture |
Get-Date
Get-EventLog Get-ExecutionPolicy Get-Help Get-History Get-Host Get-Item Get-ItemProperty Get-Location Get-Member Get-PfxCertificate Get-Process Get-PSDrive Get-PSProvider Get-PSSnapin Get-Service Get-TraceSource Get-UICulture Get-Unique Get-Variable Get-WmiObject Group-Object Import-Alias Import-Clixml Import-Csv Invoke-Expression Invoke-History Invoke-Item Join-Path Measure-Command Measure-Object Move-Item |
Move-ItemProperty
New-Alias New-Item New-ItemProperty New-Object New-PSDrive New-Service New-TimeSpan New-Variable Out-Default Out-File Out-Host Out-Null Out-Printer Out-String Pop-Location Push-Location Read-Host Remove-Item Remove-ItemProperty Remove-PSDrive Remove-PSSnapin Remove-Variable Rename-Item Rename-ItemProperty Resolve-Path Restart-Service Resume-Service Select-Object Select-String Set-Acl Set-Alias |
Set-AuthenticodeSignature
Set-Content Set-Date Set-ExecutionPolicy Set-Item Set-ItemProperty Set-Location Set-PSDebug Set-Service Set-TraceSource Set-Variable Sort-Object Split-Path Start-Service Start-Sleep Start-Transcript Stop-Process Stop-Service Stop-Transcript Suspend-Service Tee-Object Test-Path Trace-Command Update-FormatData Update-TypeData Where-Object Write-Debug Write-Error Write-Host Write-Output Write-Progress Write-Verbose Write-Warning |
PowerShell Cmdlet syntax
There are a number
of parameters possible for cmdlets and a detailed discussion of syntax is
beyond our scope. I will try to hint at the range of possibilities by
discussing one useful cmdlet that carries out the copying function. It is not
limited to copying files and folders but can also copy Registry keys and
entries. This one cmdlet, in fact, incorporates the functions of several older
commands with greater flexibility. First, here is a simple example where a
folder and all its contents are to be copied
Copy-Item
C:\Logfiles -destination D:\Backup -recurse
This cmdlet copies all files and sub-folders in the folder C:\Logfiles to the
folder D:\Backup .The parameter "-recurse" is used when sub-folders
are to be copied.
Next, here are all
the parameters in their full glory:
Copy-Item
[-path] [[-destination] ] [-container]
[-recurse] [-force]
[-include ] [-exclude ]
[-filter ] [-passThru] [-credential ]
[-whatIf] [-confirm] []
Naturally, the full set of parameters varies from one cmdlet to the next but
one option that is common to many is the intriguing "-whatIf". This
setting describes what would happen if you executed the command but without
actually executing it .This allows you to see safely what would happen if you
did the command. For a table describing the various parameters above, click here.PowerShell Scripting
PowerShell is also
the basis for a scripting language. An overview of the available operators and
functions is at this MSDN reference.
This language is intended to make administrative tasks easier and seems likely
to supplant VBScript in the future. The extension for PowerShell scripts is .PS1. Many security
features are built into the scripting engine and the default setting is to
prevent scripts from running. Permission to run scripts is controlled by a
feature called "Execution Policy". Information about this feature can
be obtained by the PowerShell command
Get-Help
about_signing
More about
PowerShell scripting can be found at this Microsoft site. More information
We
can barely scratch the surface in ths very short description of PowerShell. For
those who wish to explore the subject further, here are some references:
The
Recovery Console in Windows XP
A
special example of a command-line accessory is the Windows XP Recovery Console,
which can be a great help if Windows needs repairing and won't boot, especially
for NTFS machines.
Even if you never
intend to use the command line, it would pay to become familiar with the
Recovery Console. In the event of a problem getting Windows XP to boot, this
command line facility might allow you to repair a corrupted system or to
retrieve precious personal files. In FAT systems, a DOS boot disk can be used to access a
system with problems but the NTFS systems that are now common cannot be
accessed from DOS. As outlined on another
page, various CD boot disks can be constructed that provide for
emergency services either with Linux or special NTFS readers. However, Windows
XP comes with its own accessory for this purpose. The Recovery Console will
work with both FAT and NTFS formatted disks but is especially useful for
systems with NTFS. It is not as well known as it should because Microsoft seems
to want to keep it obscure and hard to use. In this article, I will try to
clarify its usage and explain how it can help the average PC owner.
Accessing the Recovery Console with a Windows CD
If
you have a full Windows disk, the console can be accessed by booting from the
Windows XP CD. It will take its time loading the setup but eventually you will
see the “Welcome to Setup” screen. Enter the letter “r” and a prompt will
appear asking for the administrator password. Users of the Home edition or
those without an administrator password can just enter a blank. (Note that this
password is not necessarily the same as the one for a user account, even if
that account has administrator privileges). The screen will then show a
numbered list of all your Windows installations (most people will have only
one.) It will ask, "Which Windows installation would you like to log
onto?" Unless you have a multi-boot system, enter the number
"1". You must enter a number. Do NOT just press the Enter key. Some
time may pass but eventually the Recovery Console will load and provide a
command prompt where various system tasks can be performed.
Accessing the Recovery Console Without a Windows CD
Computer vendors
very often do not provide a Windows disk with their systems. Instead they
provide a Restore disk or just a hidden restore
partition. They may
provide a way to get into the Recovery Console but computer owners will have to
check their particular setup. If, as is likely, the Recovery Console is missing
there is another way to obtain it.
Microsoft provides
software for creating a set of six diskettes for reinstalling Windows XP for
those with no bootable CD.The details are here. It
doesn't seem to be widely known but these disks also contain the Recovery
Console. Thus creating this set of diskettes will give those without a Windows
CD (but with a floppy drive) the option of using the Recovery Console. It is
tedious; you have to wait while the system slogs through the setup process and
loads all six disks but if it saves your system it will be worth it. Once you
get to the Welcome Screen. the procedure is the same as with that with a CD
described above.
If you have neither
a Windows XP CD nor a floppy drive, there are methods for placing floppy disk
images on a bootable CD. One easy way to create a bootable CD containing the
Recovery Console from the Microsoft file mentioned above has been provided by
Dean Adams and can be downloaded at this link.
Commands in the Recovery Console
Once you have opened
the Recovery Console, what can you do with it? Table I lists commands that are
available. Many have switches. Details about syntax and functions are available
on a following page or can be obtained by
entering {command}
/?
in the Recovery Console. Details are also available on this Microsoft page. Note that the console
has its own command interpreter and commands may differ somewhat from those of
the same name in a regular command prompt. Also, in the default configuration,
some commands are disabled or limited in their functions. Removing some of the
restrictions is discussed in the next section.
Table I. Available
commands in the Recovery Console
|
|
Command
|
Description
|
Attrib
|
Changes the attributes of a file or
directory
|
Batch
|
Executes the commands specified in the
text file
|
Bootcfg
|
Boot file (boot.ini) configuration and
recovery
|
ChDir (Cd)
|
Displays the name of the current directory
or changes the current directory
|
Chkdsk
|
Checks a disk and displays a status report
|
Cls
|
Clears the screen
|
Copy
|
Copies a single file to another location
|
Delete (Del)
|
Deletes one or more files
|
Dir
|
Displays a list of files and
subdirectories in a directory
|
Disable
|
Disables a system service or a device
driver
|
Diskpart
|
Manages partitions on your hard drives
|
Enable
|
Starts or enables a system service or a
device driver
|
Exit
|
Exits the Recovery Console and restarts
your computer
|
Expand
|
Extracts a file from a compressed file
|
Fixboot
|
Writes a new partition boot sector onto
the specified partition
|
Fixmbr
|
Repairs the master boot record of the
specified disk
|
Format
|
Formats a disk
|
Help
|
Displays a list of the commands you can
use in the Recovery Console
|
Listsvc
|
Lists the services and drivers available
on the computer
|
Logon
|
Logs on to a Windows installation
|
Map
|
Displays the drive letter mappings
|
Mkdir (Md)
|
Creates a directory
|
More
|
Displays a text file
|
Rename (Ren)
|
Renames a single file
|
Rmdir (Rd)
|
Deletes a directory
|
Set
|
Displays and sets environment variables
|
Systemroot
|
Sets the current directory to the
systemroot directory of the system you are currently logged on to.
|
Type
|
Displays a text file
|
Removing Console Restrictions
The default
configuration of the console contains a number of limitations. I presume the
rationale behind this is to limit the damage that the uninitiated might do.
However, it greatly reduces the usefulness of the console. The restrictions
include denial of access to any but a limited number of folders, inability to
write to a floppy disk, and inability to use wild cards in commands. These
restrictions can be removed by several methods. They are described in the next
three sections. Note that these measures must be taken from a regular Windows
logon with administrator privileges. They cannot be made from the Recovery
Console itself.
Using the Group Policy or Security Policy Management Consoles
This method is open
to Windows XP Professional users only and involves a section of the Group
Policy Editor called Local Security Settings. A description is given at this Microsoft article but
it is not a model of clarity. ( Microsoft instructions in this area are
confusing in general.) There are two possible management consoles that can be
used, the Group Policy editor gpedit.msc
or its subsection secpol.msc
(See this reference for a discussion of management consoles.) The
simplest way is to open the Local Security Settings console by entering
secpol.msc
into
Start-Run.
Then click "Local Policies-Security Options" in the left pane. In the
list that appears in the right pane find, Recovery Console: Allow Floppy
Copy And Access To All Drives And Folders, and double-click it. The box
shown in the figure below will open. Click the button "Enabled" and
then "OK"
The name of this
setting is misleading. There is more involved than enabling writing to a floppy
or access to all folders. What this actually does is to give you permission to
use the "Set" command within the Recovery Console. This command is
discussed later and is what is actually used to remove restrictions.
Editing the Registry
The procedure
described above works by changing an entry in the Registry. If you are familiar
with Registry editing, direct editing is another route and it has the advantage
of being available to those with the Home Edition of Windows XP. Open regedit
and find HKEY_LOCAL_MACHINE\Software\Microsoft\Windows
NT\CurrentVersion\Setup\RecoveryConsole\. In the right pane,
this key will have an entry "SetCommand". Put a value of 1. This is
shown in the figure below. Be sure to back
up the Registry before doing any editing.
A script for doing the Registry edit
Editing the Registry
is not an activity for everyone. For the benefit of those who are uncertain
about editing the Registry themselves, I have created a small script that will
make the Registry change for you. For this script, I have chosen the INF
format. You may be familiar with INF files since they are the standard way to
install drivers. Click here to download setcommand.inf
(zipped). Before using it, back up the Registry or make a Restore Point. Unzip
the file anywhere that is convenient and then right-click once to open the
context menu. Click the menu item "Install". That's all there is to
it. Now your Registry has been edited. Do not use this file on Windows 98/Me
systems.
Using the "Set" Command
The Registry edit
discussed in the sections above does not actually allow you any new functions
until one more step is done within the the Recovery Console itself. The
Registry edits do not make changes. They give you permission
to make changes using the "set" command. Those who are familiar with
the regular command line will be familiar with using "set" and
environment variables. (More on this subject can be read here.) The capacities of the
Recovery Console can be expanded with four "set" commands. The first
allows access to all files and folders on the main system. In the Recovery
Console prompt enter
set AllowAllPaths
= true
The second command allows you
to copy files to removable media like floppy disks. Enterset
AllowRemovableMedia = true
The next
command allows you to use wildcards in commands like "dir" and
"del". Enterset
AllowWildCards = true
Finally, there is a
command that allows you to copy files without being prompted to continue when
you are overwriting an existing file. Enterset
NoCopyPrompt = true
There must be a
space before and after the "equals" sign in all the set commands or
they won't work. The commands are not case-sensitive. The One Command to Learn
If you learn no
other commands to use in the Recovery Console, learn this:
chkdsk
C: /r
There is more than one report on the Web of how this command
fixed a system that wouldn't boot. If you are using the console from the floppy
disk installation, chkdsk
will complain that it can't locate the file autochk.exe.
When it asks for that file's location, point it to \windows\system32.
This command will thoroughly examine your hard drive and is not a fast process
so give it time.
Recovery Console Commands
The command shell that is available
in the Recovery Console differs from the command prompt in the normal Windows
XP operating system. The available commands are discussed in this article.
A previous page discussed the Recovery Console
and the commands that are available. In this article are some additional
details about the commands.
Attrib
Changes the attributes of a file or
directory. Has different parameters from the standard command prompt. The
syntax is: attrib [+r|-r] [+s|-s] [+h|-h]
[+c|-c] [[drive:][path] filename] The
switches are described in the table below:
Switch
|
Function
|
r
|
Controls"read-only"
attribute
|
s
|
Controls"system"
attribute
|
h
|
Controls "hidden"
attribute
|
c
|
Controls compressed file attribute
|
Batch
Executes the commands specified in a
text file. If desired, the results can be sent to an output file. Not available
except when using the Recovery Console. The Syntax is: batch input_file.txt
[output_file]
Bootcfg
Used to configure boot file boot.ini.
Has different parameters from the standard command prompt. Syntax is:bootcfg /parameterThe
possible parameters are given in the table below.
Parameter
|
Function
|
add
|
Add a Windows installation to the
boot list
|
copy
|
Back up boot.ini
|
default
|
Choose the default boot entry
|
disableredirect
|
Disable redirection in the boot
loader
|
list
|
List the current entries in the
boot list
|
rebuild
|
Iterate through all Windows
installations
|
redirect
|
Enable redirection in the boot
loader
|
scan
|
Scan all disks for Windows
installations
|
CD (Chdir)
Displays the name of the current
directory or changes the current directory. No switches. Behaves somewhat
differently from command prompt.
Chkdsk
Checks a disk and displays a status
report. Has different parameters from the standard command prompt. Syntax is: chkdsk
[drive:] [/p] [/r] The switch /p makes an exhaustive check of a drive without
making changes. The switch /r makes the same check but also recovers readable
information. (Note that there are erroneous entries on the Internet that
suggest using switches that are only available in the regular command prompt.)
Cls
Clears the screen. Has same function
as in the command prompt.
Copy
Copies a single file to another
location. Lacks the switches present in the command prompt.
Del
Deletes a single file. Lacks the
switches present in the command prompt.
Dir
Displays a list of the files and
subdirectories in a directory. Lacks the switches present in the command
prompt.
Disable
Disables a system service or a
device driver. The command is only available when you are using the Recovery
Console. The syntax is: disable {[service_name] | [device_driver_name]}
Diskpart
Creates and deletes partitions on a
hard drive. The command is different from the very restricted version available
in a normal command prompt. The syntax is: diskpart [/add | /delete]
[device_name | drive_name | partition_name] [size]
Enable
Starts or enables a system service
or a device driver. The command is only available when you are using the
Recovery Console. The syntax is: enable {service_name | device_driver_name}
[startup_type]
Exit
Exits the Recovery Console and
restarts your computer.
Expand
Extracts a file from a compressed
file. Has switches that differ from the command prompt version. The syntax is: expand
source [/F:filename}] [destination] [/d] [/y] The switch /F:filename
allows you to extract a single file indicated by filename. To list the
files contained in a cabinet file without extracting them, use the switch /d.
The switch /y suppresses prompts when over-writing a file with an extracted
file.
Fixboot
Writes a new partition boot sector
to the system partition. The fixboot command is only available when you are
using the Recovery Console. Syntax is: fixboot [drive]
Fixmbr
Repairs the master boot record of
the specified disk. The fixmbr command is only available when you are using the
Recovery Console. The syntax is: fixmbr [device_name] If you do not specify a device_name,
a new master boot record will be written to the boot device, which is the drive
on which your primary system is loaded.
Format
Formats the specified drive to the
specified file system. The syntax is: format [drive:] [/q] [/fs:file-system]The
switch /q enables a quick format. The switch /fs: allows a choice of file
system.
Help
Displays a list of the commands you
can use in the Recovery Console.
Listsvc
Lists the services and drivers
available on the computer. Only available when you are using the Recovery
Console.
Logon
Logs on to a Windows installation.
Only available when you are using the Recovery Console.
Map
Displays the drive letter mappings.
Only available when you are using the Recovery Console.
Md (mkdir)
Creates a directory or subdirectory.
More
Displays a text file.
Net use
Connects a network share to a drive
letter. The net use command with different parameters is available from
the command prompt.
Rd (rmdir)
Removes (deletes) a directory. Lacks
the switches available in the command prompt.
Ren (rename)
Changes the name of a single file.
Set
Displays and sets Recovery Console
environment variables. Details are given on a previous page.
Systemroot
Sets the current directory to the
systemroot folder of the Windows installation where you are logged on. Not
available in the command prompt.
Type
Displays a text file.
Managing
the Windows Registry from the Command Prompt with Reg.exe
The
command-line utility reg.exe
is a powerful and versatile way to manage the Windows XP Registry. This article
discusses Its features and application.
Many will be
familiar with the graphical interface tool regedit.exe
that is available for editing the Windows Registry. Less familiar, however, is
the command-line utility reg.exe
that also comes with Windows XP. This accessory will do anything that regedit.exe can do and
has the additional facility of being directly usable in scripts. It is a common
tool for system administrators with many computers to manage but can also be
useful to the more experienced home PC user. I will discuss some aspects that
may be of interest to this latter group. More details can be found at this Microsoft site.
There is also information in the Windows XP Help
and Support Center.
Registry editing is
not for everybody but it is not as fearsome an operation as it is sometimes
made out to be. Just be sure to follow the iron-clad rule to back up the
Registry first before editing. There are many useful tweaks that involve a
simple Registry edit and reg.exe
provides a way that is simpler and safer in some ways than Regedit. It also
provides a way to back up keys or entire hives of the Registry into files that
can be stored off the main drive.
Like some other
command-line utilities, the reg command is a shell or console that has its own
set of sub-commands. An complete command will consist of
reg
subcommand variables
Table I lists these subcommands and some are discussed in more detail in
sections that follow. The commands can be carried out on remote networked
computers as well as the local computer but I will confine the discussion to
operations involving just the local computer.
Table I.
Subcommands for reg.exe
|
|
Subcommand
|
Function
|
add
|
Adds a new subkey or entry to the registry
|
delete
|
Deletes a subkey or entries from the registry
|
query
|
Displays the data in a subkey or a value
|
compare
|
Compares specified registry subkeys or
entries
|
copy
|
Copies a subkey to another subkey.
|
save
|
Saves a copy of specified subkeys,
entries, and values of the registry in hive (binary) format
|
restore
|
Writes saved subkeys and entries in hive
format back to the registry
|
load
|
Writes saved subkeys and entries in hive
format back to a different subkey
|
unload
|
Removes a section of the registry that was
loaded using reg load
|
export
|
Creates a copy of specified subkeys,
entries, and values into a file in REG (text) format
|
import
|
Merges a REG file containing exported
registry subkeys, entries, and values into the registry
|
Reg add
This command is used
to add keys and values to the Registry. The syntax is given by
REG
ADD KeyName [/v ValueName | /ve] [/t Type] [/s Separator] [/d Data] [/f]
Table II explains the entries.
Table II.
Parameters in REG ADD command
|
|
Parameter
|
Description
|
KeyName
|
Complete Registry key name. Uses
abbreviations HKCR, HKCU, HKLM, and HKU for root keys
|
/v ValueName
|
Adds or changes a value
|
/ve
|
Changes a key's default value
|
/t Type
|
The type of value: REG_BINARY, REG_DWORD,
REG_SZ, REG_MULTI_SZ, etc. The default is REG_SZ
|
/s Separator
|
Specifies the character used to separate
strings in REG_MULTI_SZ entries. The default is /0
|
/d Data
|
The data to assign to a value
|
/f
|
Forces overwriting of existing values with
prompting
|
REG ADD provides a
quick and simple method for adding new keys to the Registry or modifying old
ones. As an example, let's look at how to add the sub- key
"HackersAreUs" to the Local Machine Software key. The command would
be
REG ADD HKLM\Software\HackersAreUs
Now
let's add a value named "Stuff" and make it a binary entry with data
"0001". The command would be REG
ADD HKLM\Software\HackersAreUs /v Stuff /t REG_BINARY /d 0001
The two commands could have been executed as a single command but I have split
them to make the process clearer. I have used upper case for REG ADD but that
is for clarity and is not required. Reg delete
Keys and values can
be deleted in a similar but somewhat simpler fashion. The syntax is
REG
DELETE KeyName [/v ValueName | /ve | /va] [/f]
Table III describes the parameters.
Table III.
Parameters in REG DELETE command
|
|
Parameter
|
Description
|
KeyName
|
Complete Registry key name. Uses
abbreviations HKCR, HKCU, HKLM, and HKU for root keys
|
/v ValueName
|
Deletes a value
|
/ve
|
Deletes a key's default value
|
/va
|
Deletes all values from a key
|
/f
|
Forces deletion with prompting
|
Backing up and restoring the Registry
Providing
methods for backing up and restoring the Registry are some of the most
important applications for regedit.exe.
There are two file formats that can be used, either a binary format
known as a hive
file or a special text format known as a REG file. The latter format may be
more familiar since it is often used for Registry tweaks. The relevant commands
are discussed in the following sections.
Saving and restoring hive files
To
create a binary backup, use the command
REG SAVE KeyName FileName
Hive files are better for backup than REG files because they completely replace
the contents of a key when they are restored. The restore command is REG RESTORE
KeyName FileName
Exporting and importing REG files
REG
files are specially formatted text files with the extension "reg"
that are copies of one or more Registry keys. They are often encountered as a
way to carry out small Registry edits or in using Regedit.. They can also be
used for backup. The commands are
REG EXPORT KeyName FileName
and
REG IMPORT FileName
Note that when a REG file is
imported it , it is merged
with Registry entries rather than completely replacing them. Values that the
REG file does not contain are not removed. Reg Query
If you want to take
a quick look at what is contained in a particular Registry key or in a
particular value, you can use the command
REG
QUERY KeyName [/v ValueName | /ve] [/s]
The only new parameter here is /s. This switch will cause all the subkeys
and values in a key to be queried.
Running VBScript and JScript files from the Command Shell
Using the Windows script host to run
scripts from the command line is discussed. Some specific examples are given.
Windows XP comes with two interfaces
for running VBScript and JScript (Microsoft's version of JavaScript) files. The
default is a graphical user interface using Wscript.exe. However, there
is also a command-line interface, Cscript.exe. It is often more convenient
to use the command line for scripts and Windows XP actually comes with a number
of useful scripts for system administration that need to be run from the
command prompt.
Configuring the command shell to run scripts
Many scripts for computer management
are more conveniently run from the command shell so that the user does not have
to deal with the complications of windows and dialog boxes from the graphical
user interface. It can be easier to handle output in a command window. One way
to run a script in the command line is to preface the script with the
executable Cscript.exe. For example, a statement of the form cscript.exe
somescript.vbs can be entered into the command line and somescript.vbs
will then run in the command window. Note, however, that the fully qualified
path must generally be used and pathnames with spaces must be enclosed in
quotation marks. To make the script processor Cscript the default host for
scripts, enter into the command line wscript //H:cscript Scripts can be then be
run by simply entering into the command line somescript.vbs The default can be
returned to the graphical interface with the command wscript //H:wscript
Some scripts that come with Windows XP
Tucked away in
the folder \Windows\System32\ are some files in VBScript format that
most PC users have never heard of. Also included with the two system tool packages discussed on other pages are some tools that are in the form of scripts. Some of
these are really just for administrators but there are several that might be of
use to the average PC owner. They are listed below. More detail about these
scripts is in the Windows XP Help and Support Center. Running these
scripts is easier if Cscript is made the default interface.
Eventquery.vbs
Lists the events and event properties from one or more event
logs.Can be used with a filter to specify the types of events to include in or
exclude from the query.
Pagefileconfig.vbs
Enables an administrator to display and configure a system's
paging file Virtual Memory settings
Prncnfg.vbs
Configures or displays configuration information about a
printer. Used without parameters, prncnfg.vbs displays command-line
help.
Prndrvr.vbs
Adds, deletes, and lists printer drivers. Used without
parameters, prndrvr.vbs displays command-line help.
Prnjobs.vbs
Pauses, resumes, cancels, and lists print jobs. Used without
parameters, prnjobs.vbs displays command-line help.
Prnmngr.vbs
Adds, deletes, and lists printers or printer connections, in
addition to setting and displaying the default printer. Used without
parameters, prnmngr.vbs displays command-line help.
Prnport.vbs
Creates, deletes, and lists standard TCP/IP printer ports,
in addition to displaying and changing port configuration. Used without
parameters, prnport.vbs displays command-line help.
Prnqctl.vbs
Prints a test page, pauses or resumes a printer, and clears
a printer queue. Used without parameters, prnqctl.vbs displays
command-line help.
Windows Management Instrumentation Command-line (WMIC) tool
WMIC is a command-line and scripting interface that
simplifies the use of Windows Management Instrumentation (WMI). WMIC is based
on aliases. Aliases make the primary data provided by WMI available without
having to understand WMI-specific concepts.More details are at this Microsoft reference. Information is also available on a local computer by
entering into a command prompt WMIC /? One use of WMIC is to write simple
scripts to automate the management of a computer.
Useful Tools for Windows XP from the Server 2003 Resource
Kit
Many of the command-line tools from
the Windows Server 2003 resource kit can be used in Windows XP. Some are
described here.
Microsoft
provides a large assortment of command-line tools, which can be obtained in a
variety of ways. For users of Windows XP Professional, there are three major
sources. One set of "native" tools is part of the standard installation
and these are listed on another page. A second set, called "support tools", can be
installed from a full version of Windows XP Professional or downloaded. These
are the subject of this page on the present site. A third set is part of the Windows
Server 2003 Resource Kit but are applicable to Windows XP. They can be downloaded here
and are the subject of this article.
As would be
expected, the Windows 2003 Server tools are intended for large networked
systems and many are not appropriate for typical home systems. Nonetheless,
many can be useful in a simple system. I have made a somewhat arbitrary
selection of those that seem most helpful and discuss them below. Note that
some of these tools are actually graphical (GUI) tools that are opened from the
command line and this is indicated where it applies. A full list of the tools
is available at the Microsoft download site.
Once they are installed. the Help and Support Center will contain a list with
descriptions and syntax for their use.
Cdburn.exe: ISO CD-ROM Burner Tool
CDBurn is a command-line tool that allows the user to write
data images from image files located on the hard drive to a CD. The data image
can be any kind of data, even raw data. This tool can also be used to erase
CD-RW media.
Chklnks.exe: Link Check Wizard
Link Check Wizard (ChkLnks) is a GUI tool that scans all the
link (shortcut) files on a computer to determine whether or not the shortcuts
point to existing applications or documents. When Link Check Wizard does not
find an associated application or document, the wizard lists that file as a
dead link, giving you the option to remove it.
Cleanspl.exe: Spooler Cleaner
Spooler Cleaner (CleanSpl) is a GUI tool that restores the
print spooler to its original state. It deletes all print jobs, printers,
printer drivers, and spool files on a specified local or remote server.
Creatfil.exe: Create File
CreatFil creates a blank file of a specified size, filled
with space characters.
Diskraid.exe: RAID Configuration
Tool
DiskRaid is a command-line tool that enables configuration
and management of redundant array of independent (or inexpensive) disks (RAID)
storage subsystems.
Dvdburn.exe: ISO DVD Burner Tool
DVDBurn is a command-line tool that allows the user to write
DVD images from image files located on the hard drive to DVD media. The data
image can be created by any program capable of producing DVD image files. You
can also use this tool to erase DVD media.
Empty.exe: Free Working Set Tool
Free Working Set Tool (Empty) is a command-line tool that
frees the working set of a specified task or process, making those page frames
available for other processes.
Iniman.exe: Initialization Files
Manipulation Tool
IniMan is a command-line tool that enables you to add,
delete, modify, or query sections or keys in an .ini file.
Instsrv.exe: Service Installer
Service Installer (InstSrv) is a command-line tool that
installs and uninstalls executable services and assigns names to them.
Kernrate.exe: Kernel Profiling Tool
Kernel Profiling Tool (KernRate) is a command-line tool that
is a CPU sample profiler. A sample profiler monitors performance and reports
back to the user. KernRate reports on kernel and user-mode processes to provide
information about CPU activity. Use KernRate to identify which processes are
causing a CPU bottleneck.
Linkspeed.exe: Link Speed
Link Speed is a command-line tool that displays the speed of
the connection between computers on a network.
Memmonitor.exe: Memory Monitor
MemMonitor is a command-line tool that monitors the memory a
process uses
Memtriage.exe: Resource Leak Triage
Tool
MemTriage is a command-line tool that detects a possible
resource leak on a running system. MemTriage records process information or
current kernel pool information and saves it to a log file.
Now.exe: STDOUT Current Date and
Time
Now reads standard input (STDIN) and then displays, on
standard output (STDOUT), the current date and time followed by the STDIN. Used
alone, it displays the current date and time.
Ntimer.exe: Windows Program Timer
NTimer is a command-line tool that measures how long a
program runs. NTimer shows elapsed time, time in user mode, and time in
privileged mode.
Oh.exe: Open Handles
Open Handles is a command-line tool that shows the handles
of all open windows. OH can also be used to show only information about a
specific process, object type, or object name.
Oleview.exe: OLE/COM Object Viewer
OLE/COM Object Viewer (OLEView) is a GUI tool that allows
you to manage all Microsoft Component Object Model (COM) classes installed on
your computer.
Pathman.exe: Path Manager
PathMan is a command-line tool that adds or removes
components from system or user paths.
Pmon.exe: Process Resource Monitor
Process Resource Monitor (PMon) is a command-line tool that
displays several measures of the CPU and memory use of processes running on the
system. The PMon display appears in the command window.
Printdriverinfo.exe: Drivers Source
Drivers Source (PrintDriverInfo) is a command-line tool that
is used to collect information about printer drivers and is primarily used for
support purposes.
Qgrep.exe
Qgrep is a command-line tool that is used to search a file
or list of files for a specific string or pattern and return the line
containing the match. QGrep also allows you to search multiple files and
subdirectories. Qgrep is similar to the UNIX tool "grep".
Remapkey.exe: Remap Windows Keyboard
Layout
RemapKey is a GUI tool that changes the layout of a keyboard
by remapping the scan codes of the keys.
Robocopy.exe: Robust File Copy
Utility
A versatile utility for maintaining an identical copy of a
folder and its sub-folders in more than one location,
Setprinter.exe: Spooler
Configuration Tool
Spooler Configuration Tool is a command-line tool that is
used to set configurations of local and remote printers
Sleep.exe: Batch File Wait
Sleep is a command-line tool that causes the computer to
wait for a specified amount of time. For use in batch files
Splinfo.exe: Print Spooler
Information
SplInfo is a command-line tool that collects information
from the print spooler and displays it.
Tail.exe
Tail is a command-line tool that displays a user-specified number
of the last lines of a text file, such as a log file, in a console window
Managing Windows XP Services with the Service Controller
Command SC
The Service Controller utility SC is
a powerful command-line utility for managing Windows services. Its various
capabilities and functions are discussed here.
Many processes and functions of the Windows XP operating
system and other software are classified under the general rubric of
“services”. Managing services with the graphical facility called the Services
Console is discussed at a sister site. In addition to
a GUI method of managing services, Windows XP also has a powerful command-line
utility.This utility, the Service Controller, is opened by entering "sc'
into the command prompt and contains a large assembly of subcommands that we
will survey.
The command-line method of managing services has the
advantage of being available for scripts. It also allows for quickly stopping
and starting services for troubleshooting purposes. Systems administrators use
it for managing services on networks and for very detailed configuration. For
the average PC user, it provides a quick and easy way to turn services on and
off to see how system performance is affected.
The SC subcommands
The "sc" command comes with numerous subcommands. A
list can be seen at the this Microsoft page or by
entering "sc /?" into a command prompt. There is also a list in the
Windows XP Help and Support Center. Altogether, 24 subcommands are
listed. Each subcommand in turn may have a subset of different commands. The
table below shows a selection of the subcommands and their functions that are
of most relevance to a typical PC owner. Much more detailed information is
available at the XP Help and Support Center by searching "sc".
Table
I. Selected subcommands for SC
|
|
Command
|
Function
|
sc config
|
Configures service startup and
login accounts
|
sc continue
|
Resumes a paused service
|
sc enumdepend
|
Lists the services that cannot run
unless the specified service is running
|
sc failure
|
Specifies what action to take upon
failure of the service
|
sc pause
|
Pauses a service
|
sc qc
|
Displays the configuration of a
particular service
|
sc query
|
Displays information about the
specified service, driver, type of service, or type of driver
|
sc start
|
Starts a service running
|
sc stop
|
Sends a STOP request to a service
(not all will respond)
|
Examples of some useful ways to
apply SC
The suite of commands that are available are very powerful
and allow for much configuring of services. Although not all functions will be
of interest to the average PC use, some are applicable to everyday experience.
You can learn if a service is runninng, stop, start. or pause it, and determine
if it will run when the system is started up. Here are examples of some
commands that I think might be of interest.
sc config
This command has a number of
functions but one is to determine the status of a service at system startup. A
service can be set to run automatically, manually or not at all. The commands
aresc config ServiceName start= flagHere ServiceName is
the name of the service and flag has one of the values auto, demand.
or disabled . For example, to set a service to run manually the command
is sc config ServiceName start= demandNote that there must be a space
after the equals sign. The correct value for the parameter ServiceName may not
always be obvious and the next command can be used to find it for all services.
sc query
Information about services and
drivers can be obtained with this command. Used alone it returns a list of
running services with various information about the service. Lists can be
inconvenient to read on a screen and they can be redirected to a text file. To
create a text list of running services use the commandsc query >
serviceslist.txt The path for the text file serviceslist.txt can be
anywhere that is convenient. To create a list of all services, usesc query type=
service state= all > allserviceslist.txt To create a list of active drivers,
use sc query type= driver Or for a list of everything, use sc query state= all
sc start
To start up a service that is not
running, usesc start ServiceName
sc stop
To stop a running service, use sc
stop ServiceName However, some services cannot or should not be stopped.
Accessing System Folders with the Shell Command in Windows
Vista
A number of system folders in Vista
are most easily accessed with the "Shell:" command. The folders are
listed.
Sometimes it's desired to work with one of the special system
folders. As discussed on another page, Windows XP
system folders can be opened by entering the folder name in the Run
line. However, in Vista this procedure does not work. Instead, the folder name
has to be preceded with the command "shell:". Although the Run
line can still be used, it is not shown in the default Vista configuration and
the Start menu's "Start Search" line can be used instead. For
example, to open the "SendTo" folder, enter shell:sendto Note that
there must be no spaces between "shell:" and the command. Also note
the colon. The command is not case-sensitive.
The command prompt can also be used to open special system
folders with the shell command. In the command prompt the shell command must be
used in conjunction with the "start" command. For example, to open
the "Cookies" folder the command would be:start shell:cookiesThis
method of opening system folders is also applicable in Windows XP.
Below is a list of system folders that can be opened. The
list is taken from the Registry key
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\explorer\FolderDescriptions
(The list will vary somewhat depending on the version of Vista.)
Vista System Folders
AddNewProgramsFolder
Administrative Tools AppData AppUpdatesFolder Cache CD Burning ChangeRemoveProgramsFolder Common Administrative Tools Common AppData Common Desktop Common Documents Common Programs Common Start Menu Common Startup Common Templates CommonDownloads CommonMusic CommonPictures CommonVideo ConflictFolder ConnectionsFolder Contacts ControlPanelFolder Cookies CredentialManager CryptoKeys CSCFolder Default Gadgets Desktop Downloads DpapiKeys Favorites Fonts Gadgets Games GameTasks History InternetFolder Links Local AppData LocalAppDataLow LocalizedResourcesDir MAPIFolder My Music My Pictures My Video |
MyComputerFolder
NetHood NetworkPlacesFolder OEM Links Original Images Personal PhotoAlbums Playlists PrintersFolder PrintHood Profile ProgramFiles ProgramFilesX64 (in 64-bit systems) ProgramFilesX86 (in 64-bit systems) ProgramFilesCommon ProgramFilesCommonX64 (in 64-bit systems) ProgramFilesCommonX86 (in 64-bit systems) Programs Public PublicGameTasks Quick Launch Recent RecycleBinFolder ResourceDir SampleMusic SamplePictures SamplePlaylists SampleVideos SavedGames Searches SearchHomeFolder SendTo Start Menu Startup SyncCenterFolder SyncResultsFolder SyncSetupFolder System SystemCertificates SystemX86 Templates TreePropertiesFolder UserProfiles UsersFilesFolder Windows |
The
Start-Run Line
The
"Run" line in the Start menu can be used to speed up access to a
whole variety of functions. Some examples of the shortcuts that are available
are discussed here.
Introduction to the Run Line
The
Run command line may be one of the least utilized functions in the Start menu.
This is a pity since it can be very useful. It is often the quickest way to
launch programs or to open folders and documents. The figure below shows the Start-Run entry.
Clicking the entry
"Run" opens the box shown below, where commands may be typed and
entered.
Opening applications in Run
Although
applications can be opened in a variety of ways, the Run line often provides
the quickest route. Desktop shortcut icons are also a quick route but you have
to know how to create a shortcut for all the applications and you may end up
with dozens of icons.
The best candidates
for the Run line are applications that are in the "path" environment.
(Go to this page for more discussion of the path.)
The path environment is a set of folders whose names do not have to be included
when entering a command. The path environment variable normally includes \Windows\ and \Windows\system32\.
Many common accessories and Windows applets are in these folders and can be
opened by entering just the executable file name. Several that I use constantly
are the Registry editor (regedit) and the System Configuration Utility (msconfig).
Note that neither of these frequently used system tools has an entry in Start-
All Programs. The Run line is the
standard method of accessing them.
A table listing some
applications that can be opened in the Run line is given below.
A few applications
for the Run line
|
|
Entry for Run
|
Function
|
calc
|
Opens calculator
|
cmd
|
Opens command prompt window
|
explorer
|
Opens Windows explorer
|
magnify
|
Screen magnifier accessory
|
msconfig
|
System Configuration Utility
|
mshearts
|
Opens Hearts game
|
msinfo32
|
System Information applet
|
mspaint
|
Opens graphics accessory Paint
|
notepad
|
Notepad accessory
|
regedit
|
Registry editor
|
sol
|
Opens Classical Solitaire game
|
Programs not in the
path require their full address, including the root folder and all subfolders.
Actually typing long path names is not required since a "Browse"
function comes with the Run line. This provides a way to search for files of
interest and to enter them directly without typing. If desired, frequently used
programs can be added to the path environment using the methods that are
discussed in a section below.
Opening Management Consoles
Some of the
functions that I find convenient to open by means of the Run line include
various Management Consoles. For example, the disk defragmenter is opened by entering
"dfrg.msc" . I find this easier than the multi-step process involved
otherwise. A list of the appropriate file names for opening some of the various
services is given in the table below. A more complete list is
on this page.
Commands for some
Management Consoles (msc extension required)
|
|
Entry for Run
|
Function
|
ciadv.msc
|
Manages the Indexing Service
|
compmgmt.msc
|
Computer Management Console. It contains a
number of the other consoles
|
devmgmt.msc
|
Device Manager
|
dfrg.msc
|
Disk Defragmenter
|
diskmgmt.msc
|
Disk Management
|
gpedit.msc
|
Group Policy Editor. Windows XP
Professional only
|
services.msc
|
Manages the many services involved in
Windows and installed software
|
Opening Control Panel Applets
It is also possible
to use Run
to open the applets that appear in the Control
Panel. A full discussion of shortcuts to Control Panel applets is
given on this page. For example,entering
"main.cpl" launches the mouse properties window.
Rundll32.exe
There are a number
of commands employing Rundll32.exe that can be entered into Start-Run.
A full discussion can be found here.
Opening folders in Run
Not only files but
also folders can be opened in the Run line. Folders contained by a folder in
the path are in this category. Examples are folders within \Windows\ and \Windows\system32\ such
as the folders Fonts and "Drivers". Folders that
are in \Documents and
Settings\{Current User}\ can also be opened in Run. An example is SendTo (written as one word). Being able to
open this folder in Run is convenient for editing. It makes it easier to add
functions to the "Send To" entry in the right-click context menu. (See this page) Another example of a folder
from the same location that can be entered is Cookies.
Note about Vista: Certain system folders like SendTo and Cookies are not directly accessible in Vista. See the page on the Shell command.
Note about Vista: Certain system folders like SendTo and Cookies are not directly accessible in Vista. See the page on the Shell command.
There are also some
interesting shortcuts to folders that are available in Run. Typing the
backslash (\) in the run line and entering it brings up the root folder,
usually the C: drive. Typing and entering a period (.) brings up the folder \Documents and Settings\{Current
User}\ in Windows XP (or Users\(Current
User} in Vista). Entering two periods (..) opens the folder \Documents and Settings\
(or Users in
Vista).
Dragging and dropping folders and files into the Run line
If the Run line is
open (make sure it is empty) folders or files can be dragged and dropped on it
from an open folder window. The full path of the dropped object will be
inserted into the Run line and clicking "OK' or pressing the
"Enter" key will open the dropped file or folder. Although this
feature presents no particular advantage in general, it can be helpful to those
who have trouble with double-clicking the mouse.
Adding applications to the Path
The ability to enter
a short file name into the Run line to open a program can be extended to any
program by putting the folder containing the program executable into the path.
Adding folders to the path is described here.
Alternatively, the
Registry can be edited to explicitly contain the path to the desired executable
file or files. The Registry key involved is
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\App
Paths
- Create a new sub-key with the name of the executable
file that you wish to add to the path.
e .g.,
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\App Paths\somefile.exe
- In this new key, add a string variable named
"Path" containing the value of the the path to your new
executable file, e.g.,
C:\Program files\newprogramfolder\
- The new key will already have an empty variable
(Default). Edit it to have the string value of entire address of the new
program executable , e.g.,
C:\Program files\newprogramfolder\somefile.exe
You can now enter "somefile.exe" into the Run line
to open the program. An example of what the Regedit entries look like is shown
in the figure below. I have added a chess game with the executable
"winchen.exe" to the path.
A number of files
are likely to have already been added on your system. Many applications place
themselves here when they are installed. Examples are Microsoft Office
components. It is sufficient to enter "winword" into the Run line to
open Microsoft Word or "excel" to open Microsoft Excel.
Internet Applications
If you are connected
to the Internet, entering an URL into Run opens Internet Explorer (or other
browser if it is properly associated) and takes you right to the appropriate
web site. The "Browse" function can be used to go to your Favorites
folder and you can then click on a link. (Be sure the Browse function is
showing "All files" as the file type.) On some systems it will even
initiate a Web connection if you are not already on-line. You can also start
e-mail by entering “mailto:someone@somewhere.com”. This will open a blank new
e-mail with the address already entered. If you want to use an e-mail client
other than the Microsoft application Outlook Express, it will have to be
associated with the “mailto” function. Many e-mail clients do this
automatically when they are installed. (As far as I know, this does not apply
to AOL.)
Google supports a
command line function that allows for simple searches on on a single term.
Enter "www.google.com/search?q=%1" into the Run line, where %1 is the
term that is being searched. A dash can be used to combine words. For example,
try "www.google.com/search?q=windows-registry" (Omit the quotes.)
Comparison of Run with the Command Prompt
Although a great
many commands can be executed in either the Run line or a command prompt, some
commands will run directly only in one or the other. Commands which are built
into the command interpreter cannot be entered in the Run line without first
invoking cmd.exe.
They are listed here. These include commands like
"dir" and "del". Certain special features of the Run line
such as the direct way of opening folders or the Internet shortcuts discussed
above do not work in a command prompt unless prefaced with the command "Start".
Accessing the Command Shell from Run
The command
interpreter can be invoked to carry out a command from the Run line by entering
cmd /c
some_commandWith
the switch "/c", some_command
will be carried out and the command shell will then close. If you want the
command shell to remain open, use the switch "/k". Enter cmd
/k
some_commandThe Run Line in Vista
The Start menu in Vista has
no Run line in
its default setting. Many of the functions of Run can be carried out in the new Search
function that is at the bottom of the Vista Start
menu but I still like to use Run
sometimes. You can get Run back
temporarily by using the keyboard shortcut Windows key+R. To put Run permanently back in
the Start menu
:
- Right-click on the Start menu and choose "Properties"
- Select the "Start Menu" tab and click on the "Customize..." button
- Check the "Run command" option
Windows
XP SP2 Support Tools
Windows
systems come with numerous command-line tools. There are also others that can
be downloaded and installed. One group is called support tools and a number of
these are listed here. The tools are primarily for system administration but
some can also be applied to diagnosing and resolving computer problems in PCs
in the home.
The list below omits
some of the more specialized tools, such as those for Active Directory. A complete list is here
along with the free download. These tools are in addition to the large number
of command-line utilities that are part of the default installation of Windows
XP Professional. These additional tools require their own installation . (Not
available for 64-bit Windows XP.)
A Selection of Windows XP Command-Line Support Tools
- acldiag.exe- manages access control lists
- activate.exe- Windows product activation
- apmstat.exe- provides status information on Advanced Power Management (APM) features.
- bindiff.exe- shows the differences between two binary files
- bitsadmin.exe- manages the Background Intelligent Transfer Service
- browstat.exe- a general purpose character-based browser diagnostic tool
- cabarc.exe- allows users to create, query and extract Windows cabinet (CAB) files.
- depends.exe- provides way to determine which DLLs an application depends on ( also known as "Dependency Walker")
- dhcploc.exe- displays the DHCP servers active on your subnet
- diruse.exe- displays directory size information for NTFS volumes
- dmdiag.exe- displays system state and configuration information describing disk storage.
- dupfinder.exe- duplicate file finder
- efsinfo.exe- displays information about files that are encrypted with Encrypting File System (EFS) on NTFS partitions.
- extract.exe- a utility that allows you to extract all files or specific files contained within a cabinet (.cab) file
- filever.exe- displays information on the versions of executable files
- ipseccmd.exe- configures Internet Protocol Security (IPSec) policies
- memsnap.exe- takes a snapshot of the memory resources being consumed by all running processes and writes this information to a log file
- msicuu.exe- Windows Installer Clean Up Utility
- msizap.exe- removes either all Windows Installer information for a product or all products installed on a computer
- netcap.exe- monitors packets on a LAN and writes the information to a log file
- netdiag.exe- tests the network connectivity
- netset.exe- used to add, remove, or change the network configuration
- pfmon.exe- displays the faults that occur while executing a process
- pstat.exe- gives you information about the processes and drivers that are currently running on your computer.
- pviewer.exe- process viewer
- setx.exe- sets environment variables
- showaccs.exe- enables users to examine the access control lists (ACLs)
- timezone.exe- Daylight Saving Time Update Utility
- whoami.exe- displays the user name and security identifier (SID)
- windiff.exe- shows the differences between specified ASCII text files, or folders containing ASCII text files
- xcacls.exe- used to set all file-system security options that are accessible in Windows Explorer from the command line
Managing
Windows Programs from the Command Line: Tasklist
Windows
XP Professional, Vista and 7 come with a powerful command-line tool called
Tasklist that provides many details on the programs and processes that are
running.
Many will be
familiar with the graphical tool Task Manager, which I have discussed elsewhere, and which provides
various kinds of information about the applications and processes that are
running on a system. There are also several command-line tools that provide
similar but even more detailed information. In this article I will discuss the
features of the tool called Tasklist
(the system file is tasklist.exe).
This tool is part of the regular installation of the Professional version of XP
but does not come with the Home edition. However, those with the Home version
of XP can download Tasklist here.
Tasklist can be applied to see how much memory and CPU time running processes
are using, what DLL files they rely on, and other information. Thus it can be a
very useful troubleshooting tool.
Basic Tasklist command
If all you want to
know is what tasks are running, enter TASKLIST into the command line. The
output can be redirected to a file if you wish. The default format is a table
with several columns of information. An example of a partial console output is
shown in the figure below. There are five columns of information. The following
list gives the meanings of the various column headings:
Image
Name
The
name of the process or the executable file running the process.
PID
The
process ID. The system assigns a number to each process so it can keep track of
it. It is possible to have several processes running with identical names but
the PID will be unique. Note that the PID may not be the same each time you
open a particular program. You may need the PID to run certain other diagnostic
tools and Tasklist is one way to obtain this information.
Session
Name
Unless
you are on a network, this will read "Console" indicating that the
process was started locally. Home PC users can usually ignore this column.
Session#
Each
session is assigned a number. Home PC users can usually ignore this column
also.
Mem
Usage
This
gives the very useful information about how much memory (in KB) that a process
was using at the time Tasklist was run.
Additional
columns will be displayed in the so-called "verbose" mode that is
obtained with the switch
/v. These columns are:
Status
Gives
the current status of the process as "Running", "Not
Responding", or "Unknown". Useful for finding hung processes.
Unknown status may refer to a normal process but Not Responding indicates a
process that should be stopped.
User
Name
User
account under which the process is running, Windows itself will be running many
processes and the various system accounts SYSTEM, LOCAL SERVICE , or NETWORK
SERVICE. will appear, coupled with the local domain name NT AUTHORITY.
CPU
Time
The
total amount of
CPU cycle time used by the process since its start. This can be a big number if
you never turn off the computer.
Window
Title
Windows
display name of the process if it exists. Can sometimes help identify what
program is involved.
More advanced options for Tasklist
There are many more
options and these are provided by switches. The full syntax is:
TASKLIST
[/S system [/U username [/P [password]]]] [/M [module] | /SVC | /V] [/FI
filter] [/FO format] [/NH]
Upper case
has been used for clarity but the command is not case-sensitive. Table I
describes the various parameters.
Table I.
Parameters for TASKLIST
|
|
Parameter
|
Description
|
/S system
|
Specifies the remote system to connect to.
Not needed for local computer
|
/U username
|
Specifies the user context. Not needed for
local computer
|
/P [password]
|
Specifies the password for the given user
context (if necessary).
|
/M [module]
|
Lists all tasks that have DLL modules
loaded in them that match the given pattern name. If the module name is not
specified, displays all modules loaded by each task.
|
/SVC
|
Displays services in each process.
|
/V
|
Specifies that the verbose information is
to be displayed.
|
/FI filter
|
Displays a set of tasks that match a given
criteria specified by the filter.
|
/FO format
|
Specifies the output format. Valid values:
"TABLE", "LIST", "CSV".
|
/NH
|
Specifies that the "Column
Header" should not be displayed in the output. Valid only for
"TABLE" and "CSV" formats.
|
These additional
parameters enable Tasklist to provide very detailed information about the
system. Some examples will be shown in the next sections.
Find which Services use a process
It
can be very useful to know the relationship between a process and the services
that are running on a system (for a discussion of services see this page.) To obtain a table relating
Image Name, PID, and Services use the command
tasklist /svc >list.txt
Here
I have shown the redirect to a file to illustrate creating a text record. One
application of this command is for diagnosing problems with a service by
monitoring the memory usage and other properties of the processes associated
with the service. Find which DLL files are used by a process
Processes
can be using many different DLL files by calling on various procedures from
their libraries. It is not uncommon for a problem to arise because a DLL is
corrupted or is the wrong version. To find which DLLs are used by each process
use the command
tasklist /m
This will return a
table relating Image Name, PID, and Modules. "Modules" here indicates
DLLs. The table may have quite a few entries and the list can be limited to a
specific DLL by using its name in the command. For example, to see only the
processes that use oleaut32.dll,
entertasklist /m oleaut32.dll
Filtering Tasklist output
The output can be
narrowed down to specific parameters by using filters and the switch /FI.
There are a number of comparison operators and these are given in Table II. Not
all operators can be used with every parameter and allowed values are shown for
the most useful parameters in Table III.
Table II.
Comparison operators for filters
|
|
Operator
|
Description
|
eq
|
Equals
|
ne
|
Does not equal
|
gt
|
Greater than. Only used with numeric
values
|
lt
|
Less than. Only used with numeric values
|
ge
|
Greater than or equal to. Only used with
numeric values
|
le
|
Less than or equal to. Only used with
numeric values
|
Table III. Filter
operators and allowed values
|
||
Parameter
|
Valid operators
|
Valid values
|
ImageName
|
eq, ne
|
Any valid string
|
PID
|
eq, ne, gt, lt, ge, le
|
Any valid positive integer
|
MemUsage
|
eq, ne, gt, lt, ge, le
|
Any valid positive integer in kilobytes
|
Status
|
eq, ne
|
Running, Not Responding, Unknown
|
Username
|
eq, ne
|
Any valid user name (includes SYSTEM,
LOCAL SERVICE , NETWORK SERVICE)
|
WindowTitle
|
eq, ne
|
Any valid string
|
An example of using
a filter is a command to find processes that are not responding. The command
would be
tasklist /fi "status eq not
responding"
Another example is
to find processes using a lot of memory, say more than 40 MB. The command is tasklist
/fi "memusage gt 40000"
A final example
shows how to clarify the multiple entries for the process
"svchost.exe" that occur. (Each has a different PID.) Service Host
(svchost.exe) is a basic piece of the Windows XP OS that is involved with many
low-level system services. These are placed in several service groups, all
running under the generic service name "svchost.exe" .(See the discussion here.) To see which
services are associated with each instance of svchost.exe, use the command
tasklist
/svc /fi "imagename eq svchost.exe"
More infornation on
Tasklist is at this Microsoft site.
Tips
for Using the Windows Command Prompt
Here's
an assortment of tips and tricks for using the Windows command shell.
There
are certain little tricks that books on the command prompt don't always tell
you. Or, if they do, the description is buried away in a paragraph somewhere.
Experienced users of the command line know all about these. However, average
users may not and I am going to mention a few useful tips for them. As far as I
know the tips work in both Windows XP and Vista except where noted. They may or
may not work for older editions of Windows. Tips for Vista only are given on
another page.
How to make a blank line in a batch file
Sometimes
you would like a blank line or two in the output from a batch file. It isn't
immediately clear how to do this. Simply entering "echo" doesn't work
because that will output the status of command echoing. The trick is to enter echo.Note that
"echo" is followed by a period with no space in between.
Force the "echo" command not to parse arguments
The
preceding tip is a special case of a more general method for using the
"echo" command. Although the command is used to display text or
messages, it can also take certain arguments such as "on" or
"off". If you write
echo off
you will not
get a display of the string "off" but will actually be configuring
the "echo" command itself. To display the string "off", you
would use echo. off
In other words, placing a period at the
end of "echo" forces the command to simply display whatever follows
without checking to see if the string is one of the special cases. Check if a file exists
A
special variant of the "If" statement can be used to
find out if a file is already present. The statement is
if exist
somefile somecommand The
statement can also test for non-existence of a file with if not
exist
somefile
somecommand The useful device "nul"
The invisible null
device called "nul" has a number of uses. (It's also sometimes called
the "bit bucket" or the "black hole".) Anything sent to it
disappears. It can be used in statements when you do not want output to be dIsplayed.
For example the command
somecommand >
nul
will carry out some command but send whatever is the normal
output into oblivion. Sometimes in a batch file you do not want any possible
error messages to be displayed. This is done by using somecommand
2> nul
Stopping a runaway command
Sometimes
you start a command only to find that it is going on and on, spewing out screen
after screen of output. Most of the time you can terminate a command by
simultaneously pressing the two keys "Ctrl" and "c".
Pausing a scrolling screen
If
you have a command with a lot of output,, you can pause the scrolling so that
you can read what's on the screen. Use the keyboard combination
"Ctrl+s". To resume scrolling, repeat Ctrl+s
Use drag and drop
Having
to type the fully qualified path of a file every time it's needed in a command
can be tedious and subject to error. Many people are unaware that a file can be
dragged from a folder or Windows Explorer view and dropped on an open command
window. It saves a lot of typing. (Doesn't work in Vista)
Go up one level above the working directory
Any
Unix user knows this one but it's often new to Windows users. To go up to the
directory that is one level above the working directory, enter
%USERPROFILE%)
cd ..
You can repeat this to go up more levels. It's a little off the subject of the
command shell but in the Start-Run
line just entering the two periods ".." will also take you up one
level from the default working directory (the working directory is normally%USERPROFILE%)
How to change the working directory to a folder on a different drive
If you want to
change the working directory for a command window to a folder on a different
drive, the command "cd" doesn't work. You have to first enter the
drive letter and colon and then enter "cd" and the folder path.
However, you can use the switch
/d to change the current working directory drive as shown below:
cd
/d E:\test
You can also make the change
with one command entry if you use "pushd" instead of "cd": pushd
E:\test
Watch out for spaces in file and folder names
The command shell does
not recognize spaces in path names. Any path name with spaces must be enclosed
in quotation marks. This problem often crops up in scripts where certain
environment variables or input arguments are used. For safety, variables that
involve file or folder names should be enclosed in quotes.
Special treatment of variables in "For" statements in batch files
"For" statements are very useful,
providing powerful iterative methods. They have the peculiarity, however, of
requiring double percent signs for iteration variables in batch files. in other
words the syntax in a batch file is:
for
%%
variable
In
set
Do
statementIf
a "For" loop is run directly from the command line, only a single
percent sign is used. The syntax is then: for
%
variable
In
set
Do
statementCase-sensitive variables in "For" statements
In contrast to Unix
systems, Windows is usually not case-sensitive, However, iteration variables in
"For" statements are case-dependent. So %A is a different variable
from %a.
Pin a command-line shortcut to the Start menu
If you use the
command prompt frequently, make it easily accessible. Open
Start-All Programs-Accessories
and right-click the entry "Command Prompt". Select "Pin to Start
menu" from the context menu. Or go to
\WINDOWS\system32 and right-click the command shell file cmd.exe and select
"Pin to Start menu" from the context menu.
Create a shortcut to a command
If there is a
command that you use frequently, you can create a shortcut. The trick is to use
the switch /k
so that the command prompt stays open. The entry for the shortcut should be
cmd
/k somecommand.exe
If the command also
needs switches, those can added as well. (The general details of making a
shortcut are at this page.) Open Windows Explorer from the command line
To open the current
command-line directory in a Windows Explorer window use the command
start
.
To open the directory above the current command-line
directory in a Windows Explorer window use the commandstart
..
(Windows XP only) To open My
Computer in a Windows Explorer window use the commandstart
...
Using the command "Start"
The tip given above
is an example of how the "Start" command can be used to invoke an
action or a system folder or an URL. For example, simply entering
"cookies" in the Run line will open the system folder Internet
Cookies in Windows XP (but not in Vista). However, in the command shell, you
would need to enter
start cookies
In Vista, the command has to be modified with the
Shell command and would be start
shell:cookies
Similarly, you can
open a program like Microsoft Word with the commandstart
winword
You can also open a Web page in
Internet Explorer with a command of the typestart
http://somesite.com
Save typing with file-name and folder-name completion (Tab completion)
A very useful
feature that can save a lot of typing is the name or path completion function.
This feature uses the Tab
key to complete file and folder names that you begin typing. For example, type
"a" (no quotes) into a command line and then press the Tab key.
Windows will complete your typing with the name of an existing file or folder
beginning with "a", starting in alphabetic order. Press Tab again and the next
possible file or folder will be displayed. In this way, you can cycle through
all files and folders existing in your current path that begin with a
particular character or group of characters. The keyboard pair Shift + Tab will take
you backwards in the list. The tab completion function can be used in more than
one place in a command.
Enable QuickEdit mode for the command window
Being able to cut
and paste to and from the command window is very handy but it is not enabled by
default. I use this feature frequently and I suggest that you enable it for all
command windows. The details of how to enable QuickEdit are given on
another page. Once QuickEdit is enabled, the contents of the clipboard
can be entered into a command prompt by right-clicking in the command window.
Display the Command History
The
default setting for the configuration of a command window includes
the capability for storing up to 50 previously entered commands. The command
history can be displayed by entering the "F7" key.
Use the "sleep" command in Windows XP batch files
Sometimes it is
desirable to have a batch file wait a certain amount of time before it carries
out the next command. If you download the free Windows 2003 Server tools (described
on another page), one of the available tools is sleep.exe, which provides
a way to make batch files wait a specified interval. For an interval of n seconds the command
is:
sleep
n
Copy text from the console window
Way back in the days
of DOS, it was not uncommon to enter text directly from the command window into
a file with the "copy" command. That is less common in Windows but
the capability is still there. Output from the command window or console is denoted
by CON. (It is not case-sensitve.) To copy text from the command window to a
file "sometext.txt", the sequence of statements would be
copy
con sometext.txt
First line of your desired text
some more text...
^Z
The last line
indicates the keyboard combination of the Control key and "z"
followed by pressing the Enter key. This command terminates the sequence and
sends the text to the desired file, which it creates. This particular example
places the file in the working directory but other paths can be used.Tips for the Vista command shell
Windows XP and Vista
share many of the same features in the command line. However, as to be
expected, there are some differences. Tips that are relevant to Vista only are
given on the next page.
Managing Windows XP Programs: Tskill and Taskkill
Windows XP comes with several tools
for ending programs or processes from the command line. The features and
application of Taskkill and Tskill are discussed.
Sometimes it
is desirable to end a program or a process from the command line. The process
may be hung or not responding or it may be desirable to have a script for
ending it. Both the Home and Professional version of Windows XP come with the
tool Tskill . In addition,
XP Professional has the more powerful tool Taskkill. Although
the graphical utility Task Manager can be used to terminate
programs that are hung up, the command line can be faster and easier to use.
Also, there may be situations where it is convenient to have a batch file that
can be run as a script. In addition, Taskkill is capable of sophisticated
filters
Tskill
The syntax for the command is TSKILL
processid | processname [/SERVER:servername] [/ID:sessionid | /A] [/V] The
meaning of the various parameters is given in Table I.
Table
I. Parameters for the command Tskill
|
|
Parameter
|
Description
|
processid
|
PID for process to be terminated.
Use only if processname is not used
|
processname
|
Process name to be terminated.
Wildcards can be used here . Do not use if PID is used
|
/SERVER:servername
|
Server containing processID
(default is current). Usually not needed on home PCs
|
/ID:sessionid
|
End process running under the
specified session. Often not needed on home PCs
|
/A
|
End process running under ALL
sessions (administrator privileges required)
|
/V
|
Display information about actions
being performed
|
An example of a simple command that would end Notepad would
be tskill notepad Another example is ending all the Microsoft documents that
you have open tskill winword All open Word documents will be closed but the
contents will not be saved so make sure to save important work. An
administrator can close processes that might be running in sessions started by
other users. The command tskill winword /a will close everybody's open Word
documents.
It may not always be obvious what process name to use for a
program. Usually the name of the program executable file (minus the EXE
extension) will work. One way is to use Tasklist
to find the PID and use that. Another is to use Task Manager to find the process associated
with a program. (Of course, Task Manager itself can be used to terminate a
program.).
Taskkill
A tool with more options is provided by Taskkill. The command
syntax is TASKKILL [/S system [/U username [/P[password]]]]{ [/FI filter] [/PID
processid | /IM imagename] } [/F] [/T] The various parameters are described in
Table II.
Table
II. Parameters for Taskkill command
|
|
Parameter
|
Description
|
/S system
|
Specifies the remote system to
connect to. Not needed for most home PCs
|
/U username
|
User context under which the
command should execute. Often not needed on home PCs
|
/P password
|
Password for username
|
/FI filter
|
Displays a set of tasks that match
criteria specified by the filter
|
/PID process id
|
Specifies the PID of the process
that has to be terminated. Not used when image name is given in the command
|
/IM imagename
|
Specifies the image name of the
process that has to be terminated. Wildcard '*' can be used to specify all
image names. Not used if PID is given in the command
|
/F
|
Forces the termination of all
processes
|
/T
|
Tree kill: terminates the
specified process and any child processes which were started by it
|
Parameters like the image name or the PID may not be
immediately obvious and Tasklist can be used to obtain them.
Taskkill has more options than Tskill and is accordingly more complicated to
use. For example, the simple command "Taskkill notepad" won't work.
First of all the image name is "notepad.exe" and not the program name
"notepad". Also, generally you will have to use the forcing switch.
The command to close notepad would be taskkill /im notepad.exe /f Another
example is to close down several programs at once.taskkill /f /im notepad.exe
/im mspaint.exe The Microsoft literature is not consistent about whether the /f
switch goes before or after the image name but it doesn't seem to matter.
Filtering Taskkill output
Taskkill becomes especially powerful when filters are used with
the switch "/fi". Various rules can be formed by using the comparison
operators shown in Table III.
Table
III. Comparison operators for filters
|
|
Operator
|
Description
|
eq
|
Equals
|
ne
|
Does not equal
|
gt
|
Greater than. Only used with
numeric values
|
lt
|
Less than. Only used with numeric
values
|
ge
|
Greater than or equal to. Only
used with numeric values
|
le
|
Less than or equal to. Only used
with numeric values
|
Table IV shows the variables that can be used in a filter.
Table
IV. Filter operators and allowed values
|
||
Parameter
|
Valid
operators
|
Valid
values
|
ImageName
|
eq, ne
|
Any valid string
|
PID
|
eq, ne, gt, lt, ge, le
|
Any valid positive integer
|
MemUsage
|
eq, ne, gt, lt, ge, le
|
Any valid positive integer in
kilobytes
|
CPUTime
|
eq, ne, gt, lt, ge, le
|
CPU time in the format of hh:mm:ss.
|
Session
|
eq, ne, gt, lt, ge, le
|
Session number
|
Status
|
eq, ne
|
Running, Not Responding
|
Username
|
eq, ne
|
Any valid user name (includes
SYSTEM, LOCAL SERVICE , NETWORK SERVICE)
|
WindowTitle
|
eq, ne
|
Any valid string
|
Services
|
eq, ne
|
Service name
|
Modules
|
eq, ne
|
DLL name
|
Examples of using filters in
Taskkill
With
filters, you can impose some specific set of conditions that must be met.
Filters give Taskkill considerable versatility and allow you to fine-tune the
target..Some examples are given below. Note that a specific image name or PID
does not have to be included when using filters.
Forcefully
shut down all the processes that are not responding. Can be used to make a
little batch file to shut down hung or frozen programs.
taskkill /f /fi "status eq not
responding"
Forcefully
shut down all programs using a specific DLL file named "some.dll".
This should be used with care but one application might be to stop processes
thought to be associated with a DLL from spyware or a Trojan. Use Tasklist
to see what processes are using a given DLL.
taskkill /f /fi "modules eq
some.dll"
Close down
all programs using large amounts of memory, say 40 MB. Use with care.
taskkill /f /fi "memusage gt
40000"
Close down
programs using more than 40 MB of memory but not Windows Explorer
taskkill /f /fi "imagename ne
explorer.exe" /fi "memusage gt 40000"
Variables
in the Windows command shell
Declaring
variables with the "set" command and their use is discussed.
Variables
have a core place in many scripting languages but play a lesser role in the
Windows command line. Many commands are predefined and the scope of variables
is rather limited. Nonetheless, there are important applications of the command
line where variables must be employed and in this article I will outline how
the command line uses variables.
How variables are defined with the "set" command
In one sense, there
are two categories of variables for the command line. Some might use the term
"variable" for the placeholders or arguments %1,
%2, ..%9, that are used to represent
user input in batch files. (See the discussion on this page.) However,
the term "variable" is normally reserved in command line usage for
entities that are declared as environment variables with the
"set" command. Note that this is a pretty primitive way to define
variables. For example, there is no typing. Environment variables, including
numbers, are stored as strings and operations with them have to take that into
account. Variables are declared and given a value in a single statement using
"set". .The syntax is:
set
some_variable = some_value
Variable
names are not case-sensitve and can consist of the usual alphanumeric and other
common characters. Some characters are reserved and have to be escaped. They
should be avoided. These include the symbols in
Table II on this page. Also, since these are environment variables,
their names should be enclosed in percent signs when used in references and
expressions, e.g,
%some_variable%
.
The percent signs are not used in the left side of the set statement that
declares a variable.Localizing variables
The declaration of a
variable lasts as long as the present command window is open. If you are using
a batch file that does not close its instance of the command window when the
batch file terminates, any variables that the batch file declares remain. If
you wish to localize a variable to a particular set of statements, use the
"setlocal" and "endlocal" commands. Thus. to confine a
variable declaration to a particular block of code, use:
....
setlocal
set some_variable = some_value
...
some statementsendlocal
...
Variables from user input
The "set"
command can also accept input from a user as the value for a variable. The
switch "/p"
is used for this purpose. A batch file will wait for the user to enter a value
after the statement
set /p
new_variable=
When the user has
entered the value, the script will continue. A message string to prompt for
input can also be used. For example:set
/p new_variable="Enter value "
Note
the space at the end of the prompt message. Otherwise, the prompt message and
the user-entered value will run together on the screen. It works but it looks
funny. The user may be tempted to hit the spacebar, which adds a leading space
to the input value.Arithmetic operations
The command line is
not designed for handling mathematical functions but it is possible to do some
very simple integer arithmetic with variables. A switch " /a"
was added to the "set" command to allow for some basic functions.
Primarily, the use is adding and subtracting. For example, it is possible to
increment or decrement counters in a loop. In principle, it is also possible to
do multiplication and division.but only whole numbers can be handled so the
practical use is limited. Although variables are stored as strings, the command
interpreter recognizes strings that contain only integers, allowing them to be
used in arithmetic expressions. The syntax is
set
/a some_variable=
{arithmetic
expression}The four arithmetic operators
are shown in Table I. (I have omitted a "modulus" operation, which
uses the % sign in yet another way. In my opinion this just adds difficulty to
an already quirky syntax. Using % in more than one sense can only confuse.)
Table I.
Arithmetic operators
|
|
Symbol
|
Operation
|
+
|
Addition
|
-
|
Subtraction
|
*
|
Multiplication
|
/
|
Division
|
Here is an example
of a variable %counter% being incremented:
set
/a counter=%counter%+1
This can also be
written as:set /a counter+=1
Variables in comparison statements in batch files
Variables are often
used in comparisons in conditional statements in batch files. Some of the
comparison operators that are used are given in Table I of the page on "If" statements. Because
of the somewhat loose way that the command line treats variables, it is
necessary to be careful when comparing variables. For strings, the safest way
is to quote variables. For example:
if
"%variable1%" == "%variable2%"
some_command
Windows Vista Command Line List and Reference
The list of commands available in
the command line shell for Windows Vista is similar to that for Windows XP but
with some additions. The commands and a brief explanation of their functions
are given. Some tips for their use are given on another page.
Commands in Windows Vista
Originally, Microsoft intended to incorporate a new command
shell in Vista but then decided to make the new shell a stand-alone application.
The new application is called Powershell and is described
on another page. Thus, the old command interpreter cmd.exe
has been continued although in a slightly newer version. (The Vista version is
6.0 whereas the XP version is 5.1.) Several commands are now in the standard
list that were formerly available only in Support
Tools or the Server 2003 Tools. For example, Robocopy
from Server 2003 is now included. There are also some new commands and they are
indicated with an asterisk in the list below. Note that some commands may
require administrator privileges. Running a command prompt as administrator is
described on this page. Some commands involving
specialized system or network administration have been omitted.
ASSOC Displays or modifies file
extension associations.
ATTRIB Displays or changes file attributes.
BREAK Sets or clears extended CTRL+C checking.
*BCDEDIT Sets properties in boot database to control boot loading.
CACLS Displays or modifies access control lists (ACLs) of files.
CALL Calls one batch program from another.
CD Displays the name of or changes the current directory.
CHCP Displays or sets the active code page number.
CHDIR Displays the name of or changes the current directory.
CHKDSK Checks a disk and displays a status report.
CHKNTFS Displays or modifies the checking of disk at boot time.
*CHOICE Batch file command that allows users to select from a set of options.
CIPHER Displays or alters the encryption of directories [files] on NTFS partitions.
*CLIP Redirects output of another command to the Windows clipboard.
CLS Clears the screen.
CMD Starts a new instance of the Windows command interpreter.
*CMDKEY Creates, lists and deletes stored user names and passwords or credentials.
COLOR Sets the default console foreground and background colors.
COMP Compares the contents of two files or sets of files.
COMPACT Displays or alters the compression of files on NTFS partitions.
CONVERT Converts FAT volumes to NTFS. You cannot convert the current drive.
COPY Copies one or more files to another location.
DATE Displays or sets the date.
DEFRAG Disk defragmenter accessory.
DEL Deletes one or more files.
DIR Displays a list of files and subdirectories in a directory.
DISKCOMP Compares the contents of two floppy disks.
DISKCOPY Copies the contents of one floppy disk to another.
DISKPART Displays or configures Disk Partition properties.
DOSKEY Edits command lines, recalls Windows commands, and creates macros.
DRIVERQUERY Displays current device driver status and properties.
ECHO Displays messages, or turns command echoing on or off.
ENDLOCAL Ends localization of environment changes in a batch file.
ERASE Deletes one or more files.
EXIT Quits and closes the command shell.
EXPAND Expands one or more compressed files.
FC Compares two files or sets of files, and displays the differences between them.
FIND Searches for a text string in a file or files.
FINDSTR Searches for strings in files.
FOR Runs a specified command for each item in a set.
*FORFILES Selects files in a folder for batch processing.
FORMAT Formats a disk for use with Windows.
FSUTIL Displays or configures the file system properties.
FTYPE Displays or modifies file types used in file extension associations.
GOTO Directs the Windows command interpreter to a labeled line in a batch program.
GPRESULT Displays Group Policy information for machine or user.
GRAFTABL Enables Windows to display an extended character set in graphics mode.
HELP Provides Help information for Windows commands.
*ICACLS Display, modify, backup, or restore ACLs for files and directories (more here).
IF Performs conditional processing in batch programs.
LABEL Creates, changes, or deletes the volume label of a disk.
MD Creates a directory.
MKDIR Creates a directory.
*MKLINK Creates Symbolic Links and Hard Links
MODE Configures a system device.
MORE Displays output one screen at a time.
MOVE Moves one or more files from one directory to another directory.
OPENFILES Queries, displays, or disconnects open files or files opened by network users.
PATH Displays or sets a search path for executable files.
PAUSE Suspends processing of a batch file and displays a message.
POPD Restores the previous value of the current directory saved by PUSHD.
PRINT Prints a text file.
PROMPT Changes the Windows command prompt.
PUSHD Saves the current directory then changes it.
RD Removes a directory.
RECOVER Recovers readable information from a bad or defective disk.
REM Designates comments (remarks) in batch files
REN Renames a file or files.
RENAME Renames a file or files.
REPLACE Replaces files.
RMDIR Removes a directory.
ROBOCOPY Advanced utility to copy files and directory trees
SET Displays, sets, or removes environment variables for current session.
SETLOCAL Begins localization of environment changes in a batch file.
SETX Sets environment variables.
SC Displays or configures services (background processes).
SCHTASKS Schedules commands and programs to run on a computer.
SHIFT Shifts the position of replaceable parameters in batch files.
SHUTDOWN Allows proper local or remote shutdown of machine.
SORT Sorts input.
START Starts a separate window to run a specified program or command.
SUBST Associates a path with a drive letter.
SYSTEMINFO Displays machine specific properties and configuration.
*TAKEOWN Allows an administrator to take ownership of a file (more here).
TASKLIST Displays all currently running tasks including services.
TASKKILL Kill or stop a running process or application.
TIME Displays or sets the system time.
*TIMEOUT Pauses the command processor for the specified number of seconds.More here.
TITLE Sets the window title for a CMD.EXE session.
TREE Graphically displays the directory structure of a drive or path.
TYPE Displays the contents of a text file.
VER Displays the Windows version.
VERIFY Tells Windows whether to verify that your files are written correctly to a disk.
VOL Displays a disk volume label and serial number.
*VSSADMIN Volume Shadow Copy Service administration tool
*WHERE Displays the location of files that match a search pattern.
XCOPY Copies files and directory trees.
WMIC Displays WMI information inside interactive command shell.
ATTRIB Displays or changes file attributes.
BREAK Sets or clears extended CTRL+C checking.
*BCDEDIT Sets properties in boot database to control boot loading.
CACLS Displays or modifies access control lists (ACLs) of files.
CALL Calls one batch program from another.
CD Displays the name of or changes the current directory.
CHCP Displays or sets the active code page number.
CHDIR Displays the name of or changes the current directory.
CHKDSK Checks a disk and displays a status report.
CHKNTFS Displays or modifies the checking of disk at boot time.
*CHOICE Batch file command that allows users to select from a set of options.
CIPHER Displays or alters the encryption of directories [files] on NTFS partitions.
*CLIP Redirects output of another command to the Windows clipboard.
CLS Clears the screen.
CMD Starts a new instance of the Windows command interpreter.
*CMDKEY Creates, lists and deletes stored user names and passwords or credentials.
COLOR Sets the default console foreground and background colors.
COMP Compares the contents of two files or sets of files.
COMPACT Displays or alters the compression of files on NTFS partitions.
CONVERT Converts FAT volumes to NTFS. You cannot convert the current drive.
COPY Copies one or more files to another location.
DATE Displays or sets the date.
DEFRAG Disk defragmenter accessory.
DEL Deletes one or more files.
DIR Displays a list of files and subdirectories in a directory.
DISKCOMP Compares the contents of two floppy disks.
DISKCOPY Copies the contents of one floppy disk to another.
DISKPART Displays or configures Disk Partition properties.
DOSKEY Edits command lines, recalls Windows commands, and creates macros.
DRIVERQUERY Displays current device driver status and properties.
ECHO Displays messages, or turns command echoing on or off.
ENDLOCAL Ends localization of environment changes in a batch file.
ERASE Deletes one or more files.
EXIT Quits and closes the command shell.
EXPAND Expands one or more compressed files.
FC Compares two files or sets of files, and displays the differences between them.
FIND Searches for a text string in a file or files.
FINDSTR Searches for strings in files.
FOR Runs a specified command for each item in a set.
*FORFILES Selects files in a folder for batch processing.
FORMAT Formats a disk for use with Windows.
FSUTIL Displays or configures the file system properties.
FTYPE Displays or modifies file types used in file extension associations.
GOTO Directs the Windows command interpreter to a labeled line in a batch program.
GPRESULT Displays Group Policy information for machine or user.
GRAFTABL Enables Windows to display an extended character set in graphics mode.
HELP Provides Help information for Windows commands.
*ICACLS Display, modify, backup, or restore ACLs for files and directories (more here).
IF Performs conditional processing in batch programs.
LABEL Creates, changes, or deletes the volume label of a disk.
MD Creates a directory.
MKDIR Creates a directory.
*MKLINK Creates Symbolic Links and Hard Links
MODE Configures a system device.
MORE Displays output one screen at a time.
MOVE Moves one or more files from one directory to another directory.
OPENFILES Queries, displays, or disconnects open files or files opened by network users.
PATH Displays or sets a search path for executable files.
PAUSE Suspends processing of a batch file and displays a message.
POPD Restores the previous value of the current directory saved by PUSHD.
PRINT Prints a text file.
PROMPT Changes the Windows command prompt.
PUSHD Saves the current directory then changes it.
RD Removes a directory.
RECOVER Recovers readable information from a bad or defective disk.
REM Designates comments (remarks) in batch files
REN Renames a file or files.
RENAME Renames a file or files.
REPLACE Replaces files.
RMDIR Removes a directory.
ROBOCOPY Advanced utility to copy files and directory trees
SET Displays, sets, or removes environment variables for current session.
SETLOCAL Begins localization of environment changes in a batch file.
SETX Sets environment variables.
SC Displays or configures services (background processes).
SCHTASKS Schedules commands and programs to run on a computer.
SHIFT Shifts the position of replaceable parameters in batch files.
SHUTDOWN Allows proper local or remote shutdown of machine.
SORT Sorts input.
START Starts a separate window to run a specified program or command.
SUBST Associates a path with a drive letter.
SYSTEMINFO Displays machine specific properties and configuration.
*TAKEOWN Allows an administrator to take ownership of a file (more here).
TASKLIST Displays all currently running tasks including services.
TASKKILL Kill or stop a running process or application.
TIME Displays or sets the system time.
*TIMEOUT Pauses the command processor for the specified number of seconds.More here.
TITLE Sets the window title for a CMD.EXE session.
TREE Graphically displays the directory structure of a drive or path.
TYPE Displays the contents of a text file.
VER Displays the Windows version.
VERIFY Tells Windows whether to verify that your files are written correctly to a disk.
VOL Displays a disk volume label and serial number.
*VSSADMIN Volume Shadow Copy Service administration tool
*WHERE Displays the location of files that match a search pattern.
XCOPY Copies files and directory trees.
WMIC Displays WMI information inside interactive command shell.
Tips
for Using the Vista Command Shell
Command-line
tips specific to Windows Vista are given.
For the most part,
the features of the command line are the same in Vista as they are in Windows
XP but there are some differences. (The Vista version is 6.0 whereas the XP
version is 5.1.) Here are some tips that apply only to Vista.
Run as administrator in Vista
The Windows Vista
operating system has a security feature called User Account Control that limits the privileges of users
by default. Since the command line is usually involved with administrative
tasks, you'll often want to run as an administrator. This can be done each time
by right-clicking the icon for the command prompt and choosing "Run
as" from the context menu . A more convenient way is to set the command
prompt to run with administrator privileges by default. Right-click the command
prompt shortcut icon and choose "Properties" from the context menu.
Click the "Advanced" button and put a check by "Run as
administrator". Click "OK". Note that you will still get the UAC
message when you open the command prompt.
Another way to run
the command prompt as administrator is to enter "cmd" in Start
Search and then use the keyboard combination Ctrl+Shift+
Enter.
"Open Command Window Here" in Vista
It is now easy to
open a command prompt referenced to a folder of your choice in Vista. If the Shift
key is held down while right-clicking a folder, the context
menu will contain an entry, "Open Command Window Here". Selecting
this entry will open a command prompt with the chosen folder as the reference
point for commands.
Open command window with administrator privileges anywhere
The "Run as
administrator" option mentioned above always opens with \Windows\System 32\
as the working directory. To open a command console with administrator
privileges in any directory of choice, you can add a command to the right-click
context menu. The INF file to make the appropriate Registry edit can be downloaded here. It is from the PowerToy
utility described at this link.
Send command output to the Windows clipboard with clip.exe
Vista comes with a
command-line utility clip.exe
that can be used to redirect or pipe the output of another command to the
Windows clipboard. The command uses a "pipe" and has the form:
somecommand
| clip
For example, to send a directory
listing to the clipboard, the command is: dir
| clip
Place the contents of a text file into the Windows clipboard with clip.exe
The utility clip.exe
can also be used to read a text file and place its contents in the Windows
clipboard. The command has the form:
clip
< somefile.txt
Clear the Windows clipboard with clip.exe
To clear the
contents of the Windows clip board, use a "pipe" :
echo
off | clip
The batch file command called "choice" is back in Vista
Oldtimers will remember
that DOS had a command for batch files called "choice" that allowed
for some limited user interaction. The command was then removed from 32-bit
command shells because the "set /p" option gave equivalent or better
functionality. However, "choice" is back in Vista in a new form.
Enter "choice /?" in a Vista command prompt for details about its
features.
Use the "choice" command to make a Vista batch file wait
One useful
application of the "choice" command is to make a batch file pause for
a specified period of time. The statement has the form:
choice
/T
n
/D y > nul
The switch "/T
n" specifies a wait period of n
seconds. The switch "/D y" creates a default choice of
"yes". To suppress the unwanted text output of the command, it is
redirected to the null device (nul). Use the "timeout" command to make a Vista batch file wait
Another new command
in in Vista is "timeout". It will cause the command processor to wait
for a specified number of seconds or until a key is pressed. The format is
timeout
/T
n
where n is the number of
seconds to wait. To make the command ignore any key presses, the switch
/nobreak can be added: timeout
/T
n
/nobreak
Because the command gives
output listing the time remaining, it may be necessary to use a redirect to
nul. timeout /T
n
> nul
Switch added to "Dir" to enable viewing Alternate Data Streams
NTFS files can have added information in
"streams" or "forks". These added items are normally hidden
from access by most Windows functions such as Explorer. In Vista a switch /R
has been added to the "dir" command that allows alternate data
streams to be listed.
Enable the built-in master administrator account on the log-in screen
Vista contains a
master administrator account but it is not normally visible on the log-in
screen. To enable it, open a command window with administrator privileges and
use the command
net user
administrator /active:yes
(Make sure
that you assign a password to the account.) To remove the account from the
log-in screen, use the command net
user administrator /active:no
Reduce the space used by System Restore with vssadmin
System Restore can
use up to 15% of a hard drive for its backup files (shadow storage). As hard
drives get ever bigger, that becomes a lot of space. The command
"vssadmin" can be used to administer settings for System Restore. To
control the space allocation, open a command prompt with administrator
privileges and enter
vssadmin Resize
ShadowStorage /For=C: /On=C: /Maxsize=[n]
For [n] enter the desired size in MB or GB. The units must be stated: for
example, "Maxsize=500MB" or "Maxsize=2GB". The example is
for the C: drive. WARNING!
This will delete all your old Restore Points!Find out how much space System Restore points occupy
To find out how much
space System \Restore is using, open the command prompt as administrator and
enter
vssadmin list shadowstorage
Increase the file system memory cache with fsutil
If you tend to open
and close a lot of files, you may be able to increase performance by creating a
larger value for a special cache setting with the file
system utility command
fsutil
behavior set memoryusage 2
According to Microsoft, this increases
something called the "paged pool" memory. Do not use if you are
already consuming large amounts of system memory with other activities. If
performance after the change is unsatisfactory, undo it with the commandfsutil
behavior set memoryusage 1
These
commands require administrator privileges. The commands change a Registry
setting and take effect after a reboot. Use "takeown" to access certain files
Vista protects many
system files for security reasons and even an administrator is not allowed to
access them. If you are denied access to a file while in an administrator
account, you can use the command line tool "takeown.exe" to reassign
ownership. You will need to run the command from a command prompt with
administrator privileges. The syntax is
takeown
/f some_file [/a] [/r]
The specified
filename can contain wildcards. You can also specify a folder. The optional
switch "/a" transfers ownership to the administrators group. If
omitted, the default is to transfer ownership to the present user account. The
switch "/r" recurses subdirectories. Although this command assigns
ownership, it does not give control rights. Thus if you wish to modify a system
file (often not a good idea) you will probably have also to apply the
"icacls" command discussed next.Obtain control rights to a file with "icacls"
(Icacls.exe
supersedes the "cacls" command of Windows XP. The older command is
still available, however.) This command has a rather complex set of options.
They can be displayed by entering "icacls /?" in a command prompt.
One example is the command to grant full access rights to an account named user:
icacls
file_name /grant user:F
Clean up Vista SP1 files
When you install
Vista service pack 1, a facility for uninstalling it is also created. If you
have SP1 installed for a while and are satisfied that you will keep it, you can
remove the uninstall files and free up almost a GB of disk space. To remove the
backup files, use the command
VSP1CLN.EXE
(I have used caps to make the difference between "one" and
"ell" clear but case doesn't matter.) Administrator privileges are
required. After running this command, you will be unable to uninstall Vista SP1
so be sure you really want to keep it. Using drag and drop- not
The useful
capability to drag commands and drop them into a command prompt that was
present in past versions of Windows does not work in Vista. (However, it has
been restored in Windows 7.)
Windows 7 Command Line List and Reference
The list of commands available in
the command prompt for Windows 7 is similar to that for Windows Vista. Some
commonly used commands and a brief explanation of their functions are given.
Commands in Windows 7
The command prompt that has been in previous versions of
Windows is still with us and is not much changed fron Windows Vista. The
command line remains a powerful and much used feature by system administrators
everywhere. Thus, the old command interpreter cmd.exe has been continued
although in a slightly newer version. Several commands are now in the standard
list that were formerly available only on servers. New commandsare indicated
with an asterisk in the list below. Note that some commands may require administrator
privileges. A number of commands involving specialized system or network
administration have been omitted.
The commands given below remain in wide use but Microsoft has
shifted its corporate emphasis to a new command shell called Powershell that is
described on another page. This new command shell is
included with Windows 7.
ASSOC
Displays or modifies file extension associations.
ATTRIB Displays or changes file attributes.
BREAK Sets or clears extended CTRL+C checking.
BCDBOOT* Used to copy critical files to the system partition and to create a new system BCD store.
BCDEDIT Sets properties in boot database to control boot loading.
CACLS Displays or modifies access control lists (ACLs) of files.
CALL Calls one batch program from another.
CD Displays the name of or changes the current directory.
CHCP Displays or sets the active code page number.
CHDIR Displays the name of or changes the current directory.
CHKDSK Checks a disk and displays a status report.
CHKNTFS Displays or modifies the checking of disk at boot time.
CHOICE Batch file command that allows users to select from a set of options.
CIPHER Displays or alters the encryption of directories [files] on NTFS partitions.
CLIP Redirects output of another command to the Windows clipboard.
CLS Clears the screen.
CMD Starts a new instance of the Windows command interpreter.
CMDKEY Creates, lists and deletes stored user names and passwords or credentials.
COLOR Sets the default console foreground and background colors.
COMP Compares the contents of two files or sets of files byte-by-byte
COMPACT Displays or alters the compression of files on NTFS partitions.
CONVERT Converts FAT volumes to NTFS. You cannot convert the current drive.
COPY Copies one or more files to another location.
DATE Displays or sets the date.
DEFRAG Disk defragmenter accessory.
DEL Deletes one or more files.
DIR Displays a list of files and subdirectories in a directory.
DISKCOMP Compares the contents of two floppy disks.
DISKCOPY Copies the contents of one floppy disk to another.
DISKPART Displays or configures Disk Partition properties. A separte command interpreter with a sub-set of commands.
DOSKEY Edits command lines, recalls Windows commands, and creates macros.
DRIVERQUERY Displays current device driver status and properties.
ECHO Displays messages, or turns command echoing on or off.
ENDLOCAL Ends localization of environment changes in a batch file.
ERASE Deletes one or more files.
EXIT Quits and closes the command shell.
EXPAND Expands one or more compressed files.
FC Compares two files or sets of files, and displays the differences between them.
FIND Searches for a text string in a file or files.
FINDSTR Searches for strings in files.
FOR Runs a specified command for each item in a set.
FORFILES Selects files in a folder for batch processing.
FORMAT Formats a disk for use with Windows.
FSUTIL Displays or configures the file system properties.
FTYPE Displays or modifies file types used in file extension associations.
GOTO Directs the Windows command interpreter to a labeled line in a batch program.
GPRESULT Displays Group Policy information for machine or user.
GRAFTABL Enables Windows to display an extended character set in graphics mode.
HELP Provides Help information for Windows commands.
ICACLS Display, modify, backup, or restore ACLs for files and directories (more here).
IF Performs conditional processing in batch programs.
IPCONFIG Displays all current TCP/IP network configuration values
LABEL Creates, changes, or deletes the volume label of a disk.
MD Creates a directory.
MKDIR Creates a directory.
MKLINK Creates Symbolic Links and Hard Links
MODE Configures a system device.
MORE Displays output one screen at a time.
MOVE Moves one or more files from one directory to another directory.
OPENFILES Queries, displays, or disconnects open files or files opened by network users.
PATH Displays or sets a search path for executable files.
PAUSE Suspends processing of a batch file and displays a message.
POPD Restores the previous value of the current directory saved by PUSHD.
PRINT Prints a text file.
PROMPT Changes the Windows command prompt.
PUSHD Saves the current directory then changes it.
RD Removes a directory.
RECOVER Recovers readable information from a bad or defective disk.
REM Designates comments (remarks) in batch files
REN Renames a file or files.
RENAME Renames a file or files.
REPLACE Replaces files.
RMDIR Removes a directory.
ROBOCOPY Advanced utility to copy files and directory trees
SET Displays, sets, or removes environment variables for current session.
SETLOCAL Begins localization of environment changes in a batch file.
SETX Sets environment variables.
SC Displays or configures services (background processes).
SCHTASKS Schedules commands and programs to run on a computer.
SHIFT Shifts the position of replaceable parameters in batch files.
SHUTDOWN Allows proper local or remote shutdown of machine.
SORT Sorts input.
START Starts a separate window to run a specified program or command.
SUBST Associates a path with a drive letter.
SYSTEMINFO Displays machine specific properties and configuration.
TAKEOWN Allows an administrator to take ownership of a file (more here).
TASKLIST Displays all currently running tasks including services.
TASKKILL Kill or stop a running process or application.
TIME Displays or sets the system time.
TIMEOUT Pauses the command processor for the specified number of seconds.More here.
TITLE Sets the window title for a CMD.EXE session.
TREE Graphically displays the directory structure of a drive or path.
TYPE Displays the contents of a text file.
VER Displays the Windows version.
VERIFY Tells Windows whether to verify that your files are written correctly to a disk.
VOL Displays a disk volume label and serial number.
VSSADMIN Volume Shadow Copy Service administration tool
WHERE Displays the location of files that match a search pattern.
XCOPY Copies files and directory trees.
WMIC Displays WMI information inside interactive command shell.
ATTRIB Displays or changes file attributes.
BREAK Sets or clears extended CTRL+C checking.
BCDBOOT* Used to copy critical files to the system partition and to create a new system BCD store.
BCDEDIT Sets properties in boot database to control boot loading.
CACLS Displays or modifies access control lists (ACLs) of files.
CALL Calls one batch program from another.
CD Displays the name of or changes the current directory.
CHCP Displays or sets the active code page number.
CHDIR Displays the name of or changes the current directory.
CHKDSK Checks a disk and displays a status report.
CHKNTFS Displays or modifies the checking of disk at boot time.
CHOICE Batch file command that allows users to select from a set of options.
CIPHER Displays or alters the encryption of directories [files] on NTFS partitions.
CLIP Redirects output of another command to the Windows clipboard.
CLS Clears the screen.
CMD Starts a new instance of the Windows command interpreter.
CMDKEY Creates, lists and deletes stored user names and passwords or credentials.
COLOR Sets the default console foreground and background colors.
COMP Compares the contents of two files or sets of files byte-by-byte
COMPACT Displays or alters the compression of files on NTFS partitions.
CONVERT Converts FAT volumes to NTFS. You cannot convert the current drive.
COPY Copies one or more files to another location.
DATE Displays or sets the date.
DEFRAG Disk defragmenter accessory.
DEL Deletes one or more files.
DIR Displays a list of files and subdirectories in a directory.
DISKCOMP Compares the contents of two floppy disks.
DISKCOPY Copies the contents of one floppy disk to another.
DISKPART Displays or configures Disk Partition properties. A separte command interpreter with a sub-set of commands.
DOSKEY Edits command lines, recalls Windows commands, and creates macros.
DRIVERQUERY Displays current device driver status and properties.
ECHO Displays messages, or turns command echoing on or off.
ENDLOCAL Ends localization of environment changes in a batch file.
ERASE Deletes one or more files.
EXIT Quits and closes the command shell.
EXPAND Expands one or more compressed files.
FC Compares two files or sets of files, and displays the differences between them.
FIND Searches for a text string in a file or files.
FINDSTR Searches for strings in files.
FOR Runs a specified command for each item in a set.
FORFILES Selects files in a folder for batch processing.
FORMAT Formats a disk for use with Windows.
FSUTIL Displays or configures the file system properties.
FTYPE Displays or modifies file types used in file extension associations.
GOTO Directs the Windows command interpreter to a labeled line in a batch program.
GPRESULT Displays Group Policy information for machine or user.
GRAFTABL Enables Windows to display an extended character set in graphics mode.
HELP Provides Help information for Windows commands.
ICACLS Display, modify, backup, or restore ACLs for files and directories (more here).
IF Performs conditional processing in batch programs.
IPCONFIG Displays all current TCP/IP network configuration values
LABEL Creates, changes, or deletes the volume label of a disk.
MD Creates a directory.
MKDIR Creates a directory.
MKLINK Creates Symbolic Links and Hard Links
MODE Configures a system device.
MORE Displays output one screen at a time.
MOVE Moves one or more files from one directory to another directory.
OPENFILES Queries, displays, or disconnects open files or files opened by network users.
PATH Displays or sets a search path for executable files.
PAUSE Suspends processing of a batch file and displays a message.
POPD Restores the previous value of the current directory saved by PUSHD.
PRINT Prints a text file.
PROMPT Changes the Windows command prompt.
PUSHD Saves the current directory then changes it.
RD Removes a directory.
RECOVER Recovers readable information from a bad or defective disk.
REM Designates comments (remarks) in batch files
REN Renames a file or files.
RENAME Renames a file or files.
REPLACE Replaces files.
RMDIR Removes a directory.
ROBOCOPY Advanced utility to copy files and directory trees
SET Displays, sets, or removes environment variables for current session.
SETLOCAL Begins localization of environment changes in a batch file.
SETX Sets environment variables.
SC Displays or configures services (background processes).
SCHTASKS Schedules commands and programs to run on a computer.
SHIFT Shifts the position of replaceable parameters in batch files.
SHUTDOWN Allows proper local or remote shutdown of machine.
SORT Sorts input.
START Starts a separate window to run a specified program or command.
SUBST Associates a path with a drive letter.
SYSTEMINFO Displays machine specific properties and configuration.
TAKEOWN Allows an administrator to take ownership of a file (more here).
TASKLIST Displays all currently running tasks including services.
TASKKILL Kill or stop a running process or application.
TIME Displays or sets the system time.
TIMEOUT Pauses the command processor for the specified number of seconds.More here.
TITLE Sets the window title for a CMD.EXE session.
TREE Graphically displays the directory structure of a drive or path.
TYPE Displays the contents of a text file.
VER Displays the Windows version.
VERIFY Tells Windows whether to verify that your files are written correctly to a disk.
VOL Displays a disk volume label and serial number.
VSSADMIN Volume Shadow Copy Service administration tool
WHERE Displays the location of files that match a search pattern.
XCOPY Copies files and directory trees.
WMIC Displays WMI information inside interactive command shell.
*New to Windows 7
Xcopy and its Application
The syntax and use of the command
"Xcopy" is described. Of all the command line executables, Xcopy is
one of the most useful for the average home PC user. It provides a powerful and
versatile method for copying and backing up files and directories.
Syntax of Xcopy command
Xcopy has a large number of possible switches, which gives
the command a great deal of flexibility. The syntax for the command is given
by:
XCOPY source
[destination] [/A | /M] [/D[:date]] [/P] [/S [/E]] [/V] [/W] [/C] [/I] [/Q]
[/F] [/L] [/G] [/H] [/R] [/T] [/U] [/K] [/N] [/O] [/X] [/Y] [/-Y] [/Z]
[/EXCLUDE:file1[+file2][+file3]...]
Upper case letters have been used above but the command is case-insensitive.
A description of the various switches is given in Table I. Note that Windows
Vista has an additional switch "/B". The function of this switch is
to copy a Symbolic Link itself instead of the target of the link. Windows 7 has
added "/J" to use unbuffered I/O for large files.
Table
I. Description of switches for the command Xcopy
|
|
Switch
|
Description
|
/A
|
Copies only files with the archive
attribute set, doesn't change the attribute.
|
/M
|
Copies only files with the archive
attribute set, turns off the archive attribute. Useful in backup.
|
/D:m-d-y
|
Copies files changed on or after
the specified date. If no date is given, copies only those files whose source
time is newer than the destination time. Useful in backup.
|
/P
|
Prompts you before creating each
destination file.
|
/S
|
Copies directories and
subdirectories except empty ones.
|
/E
|
Copies directories and
subdirectories, including empty ones. Same as /S /E. May be used to modify
/T.
|
/V
|
Verifies each new file. Not used
by Windows XP.
|
/W
|
Prompts you to press a key before
copying.
|
/C
|
Continues copying even if errors
occur.
|
/I
|
If destination does not exist and
copying more than one file, assumes that destination must be a directory.
|
/Q
|
Does not display file names while
copying.
|
/F
|
Displays full source and
destination file names while copying.
|
/L
|
Displays files that would be
copied.
|
/G
|
Allows the copying of encrypted
files to destination that does not support encryption.
|
/H
|
Copies hidden and system files
also.
|
/R
|
Overwrites read-only files.
|
/T
|
Creates directory structure, but
does not copy files. Does not include empty directories or subdirectories.
|
/U
|
Copies only files that already
exist in destination.
|
/K
|
Copies attributes. Normal Xcopy
will reset read-only attributes.
|
/N
|
Copies using the generated
"short" names. May be necessary when copying from NTFS to FAT16.
|
/O
|
Copies file ownership and ACL
information.
|
/X
|
Copies file audit settings
(implies /O).
|
/Y
|
Suppresses prompting to confirm
that you want to overwrite an existing destination file. May be preset in the
COPYCMD environment variable
|
/-Y
|
Prompts to confirm you want to
overwrite an existing destination file.
|
/Z
|
Copies over a network in
restartable mode.
|
/EXCLUDE:file1[+file2][+file3]...
|
Specifies a list of files
containing strings to be excluded. Tricky to use. See below.
|
/B
|
Copies a Symbolic Link itself
instesd of the target of the link. (Windows Vista/Windows 7)
|
/J
|
Copies using unbuffered I/O.
Recommended for very large files. (Windows 7)
|
Applications of Xcopy
Xcopy provides an excellent tool for backing up selected
folders. With appropriate switches, a variety of backup scenarios can be
created. One possible backup configuration would be to copy only those files
that have been changed. Here is an example command: xcopy C:\somefolder
E:\backupfolder /D /E /C /R /H /I /K /Y This command will copy all files,
including those in sub-folders, that are newer in the source folder. It will
copy hidden as well as read-only files and will create the destination folder
and/or sub-folders if they do not already exist.
The next example shows the use of a wildcard; it collects all
files of a given type and copies them into one place. The command xcopy
C:\*.mp3 E:\mp3folder /S /I /C > E:\mp3List.txt will collect all MP3 files
on the C: drive and copy them to a folder on the E: drive. It also creates a
list of the files copied and places the list on the E: drive. This simple
command preserves the sub-folder structure. If desired, a more advanced script
could be written that places all MP3 files in one folder with no sub-folders.
Excluding files and folders
A useful feature of Xcopy is the ability to exclude certain
files and/or folders from being copied by means of the "/Exclude"
switch. All names containing a given string of characters can be excluded.
Unfortunately, Microsoft's description
of the switch is neither a model of clarity nor accurate. In fact, postings on
the Internet indicate considerable confusion exists about how to implement this
handy feature. Perhaps the list below will help clarify how to use it.
1. The strings
contained in the names of the files and/or folders to be excluded are not
entered directly in the command switch itself.
2. The entry in
the command switch is one or more text files that list the strings to be
excluded.
3. The format
of the switch is /Exclude:{path}list_of_exclusions.txt Note the colon between
Exclude and the name of the file that lists the exclusions. Although more than
one exclusion file can be used, stick with one if you can.
4. The name of
the file that lists exclusions cannot have spaces. Quoting does not help.
5. Be careful
with pathnames. Remember that operations are relative to the working directory
for the command prompt. I suggest placing the exclusion list in the top
directory of the directories being copied and opening the command prompt in the
directory just above the directory and sub-directories to be copied. (Go
here if you don't know how to open the command prompt wherever you
want.) The various relative paths will then be simple. If you open the command
prompt in the default location, things can get complicated.
6. The
structure of the exclusions list is one exclusion string per line. Wildcards
are not used and do not work. If you want to exclude all files whose names
contain ABC, simply place ABC on one line of the exclusion file. If it is being
used together with the switch "/S", the exclusion file will apply to
sub-directories as well as the main directory.
7. To exclude a
particular sub-directory, place its name in the exclusion file with backward
slashes before and after its name, viz., \excluded_directory\
8. Use a text
editor to create exclusion files. Do not use Microsoft Word or other word
processor unless you are careful to create text files. Use ANSI encoding. When
I tried UTF-8 encoding, the file did not work.
Exit codes for Xcopy
Many commands issue integer exit codes to indicate the status
of the command after it is run. The exit codes for Xcopy are given in Table II.
When placed in "If" statements, these error
codes can be useful in batch files .
Table
II. Exit codes for Xcopy
|
|
Exit
code
|
Description
|
0
|
Files were copied without error.
|
1
|
No files were found to copy.
|
2
|
The user pressed Ctrl+C to
terminate xcopy.
|
4
|
Various errors including
insufficient memory or disk space, an invalid drive name, or invalid syntax.
|
5
|
Disk write error occurred.
|
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