Shulou(Shulou.com)06/03 Report--

What this article shares to you is about the startup parameters of cmd.exe, which the editor thinks is very practical, so I share it with you to learn. I hope you can get something after reading this article.

For example:

Editors like to use bat if running a command directly in bat will automatically close the window so that you can't see the effect, then we can add it before the command.

Cmd / k echo

You don't have to add pause every time. Because a lot of bat learning will make mistakes in many cases, so we can see the error message.

Start a new example of the command interpreter Cmd.exe. If used without parameters, cmd displays the version and copyright information of the operating system.

Grammar

Cmd [{/ c | / k}] [/ s] [/ Q] [/ d] [{/ a | / u}] [/ t:FG] [/ e: {on | off}] [/ f: {on | off}] [/ v: {on | off}] [String]

Parameters.

/ c

Execute the command specified by String, stop after execution, and exit. For example:

@ echo offcmd / c "echo% cd% & echo ddddd & set xxx=12345" pausecls

The following pause and cls will also be executed, and at the end of the execution, it will exit the current running environment (double-click the running mode), but the current environment variable xxx will not be retained (start-> run-> cmd, and then execute the current bat file. After execution, type set again to view the current environment variables)

/ k

Execute the command specified by String and continue, and the current running window and environment variables will be maintained after running. For example:

@ echo offcmd / k "echo% cd% & echo ddddd & set xxx=12345" pausecls

The program suspends execution after executing the command followed by the cmd string, so the subsequent pause and cls will not be executed. But the window and environment variables are maintained. How it works: double-click or execute the current bat file from the command line

/ s

The processing of String after modifying / c or / k.

/ q

Turn off echo.

/ d

Disables AutoRun command execution.

/ a

Format the internal command output as a pipe or file according to the American National Standards Institute (ANSI).

/ u

Formats the internal command output as a Unicode as a pipe or file.

/ t:FG

Set the foreground F color and the background G color. The following table lists valid hexadecimal digits that can be used as F and G values.

Value color 0 black 1 blue 2 green 3 light green 4 red 5 purple 6 yellow 7 white 8 gray 9 light blue A light green B light green C light red D lavender E light yellow F bright white

/ e:on

Enable command extension.

/ e:off

Disable command extension.

/ f:on

Enable file and directory name completion.

/ f:off

Disable file and directory name completion.

/ v:on

Enables delayed environment variable extension.

/ v:off

Disable delayed environment variable extension.

String

Specify the command to execute.

/?

Displays help at the command prompt.

Annotation

Use multiple commands

Multiple commands separated by the command delimiter & & can be used in String, but they must be enclosed in quotation marks (for example, "Command&& command & & command").

?

Deal with quotation marks

If you specify / c or / k _ cmd, it processes the rest of the commands in String and retains quotation marks only if all of the following conditions are met:

/ s is not used.

Accurate use of a pair of quotation marks.

No special characters are used within quotation marks (for example: & () @ ^ |).

One or more white space characters are used within quotation marks.

The String in quotation marks is the name of the executable file.

If the above conditions are not met, the first character of the String is first checked to verify that it is in left quotation marks. If the first character is a left quotation mark, it is separated from the right quote. Any text that follows the closing quotation mark is preserved.

Execute registry subkey

If / d is not specified in String, Cmd.exe looks for the following registry subkeys:

HKEY_LOCAL_MACHINE\ Software\ Microsoft\ Command Processor\ AutoRun\ REG_SZ

HKEY_CURRENT_USER\ Software\ Microsoft\ Command Processor\ AutoRun\ REG_EXPAND_SZ

If one or both of the above registry subkeys exist, they are executed before all other variables are executed.

Warning

Improper editing of the registry can seriously damage your system. Any valuable data on your computer should be backed up before changing the registry.

Enable and disable command extension

In Windows XP, command extension is enabled by default. For specific processes, you can disable them using / e:off. You can enable or disable the extension of all cmd command line options on your computer or in a user session by setting the following REG_DWORD values:

HKEY_LOCAL_MACHINE\ Software\ Microsoft\ Command Processor\ EnableExtensions\ REG_DWORD

HKEY_CURRENT_USER\ Software\ Microsoft\ Command Processor\ EnableExtensions\ REG_DWORD

Use Regedit.exe in the registry to set the REG_DWORD value to 0 × 1 (that is, enabled) or 0 × 0 (that is, disabled). User-specific settings take precedence over computer settings, and command line options take precedence over registry settings.

Warning

Improper editing of the registry can seriously damage your system. Any valuable data on your computer should be backed up before changing the registry.

When the command extension is enabled, the following commands are affected:

? assoc?call?chdir (cd)? color?del (erase)? endlocal?for?ftype?goto?if?mkdir (md)? popd?prompt?pushd?set?setlocal?shift?start (also includes external command procedures that will be changed)

For more information about these commands, see related topics.

Enable delayed environment variable extension

If delayed environment variable extension is enabled, the exclamation point character can be used instead of the runtime environment variable value.

Enable file and directory name completion

By default, file and directory name completion is disabled. For specific cmd command processing, you can enable or disable file names by / f: {on | off. You can enable or disable all file and directory name completion processed by cmd commands on your computer or in a user login session by setting the following REG_DWORD values:

HKEY_LOCAL_MACHINE\ Software\ Microsoft\ Command Processor\ CompletionChar\ REG_DWORD

HKEY_LOCAL_MACHINE\ Software\ Microsoft\ Command Processor\ PathCompletionChar\ REG_DWORD

HKEY_CURRENT_USER\ Software\ Microsoft\ Command Processor\ CompletionChar\ REG_DWORD

HKEY_CURRENT_USER\ Software\ Microsoft\ Command Processor\ PathCompletionChar\ REG_DWORD

To set the REG_DWORD value, run Regedit.exe and use the hexadecimal value of the control character for a specific function (for example, 0 × 9 for Tab key and 0 × 08 for BackSpace key). User-specific settings take precedence over computer settings, and command line options take precedence over registry settings.

Warning

Improper editing of the registry can seriously damage your system. Any valuable data on your computer should be backed up before changing the registry.

If file and directory name completion is enabled with / f:on, Ctrl+D; can be used for directory name completion and Ctrl+F can be used for file name completion. To disable a specific completion character in the registry, use the numeric value of the space [0 × 20] because the space is not a valid control character.

When you press Ctrl+D or Ctrl+F, cmd processes the file and directory names to complete the operation. The purpose of these key combinations is to append wildcards (if not already used) after the String, create a list of matching paths, and then display the first matching path. If all paths do not match, the file and directory name completion operation issues a warning sound and does not change what is displayed. To view the paths in the list of matching paths one by one, press Ctrl+D or Ctrl+F repeatedly. To view the list backwards, press Ctrl+D or Ctrl+F while pressing Shift. To discard the saved list of matching paths and generate a new list, edit String and press Ctrl+D or Ctrl+F. If you switch between Ctrl+D and Ctrl+F, the saved list of matching paths is discarded and a new list is generated. The only difference between the Ctrl+D and Ctrl+F key combinations is that Ctrl+D matches only the directory name, while Ctrl+F matches both the file name and the directory name. If you use file and directory names in any internal directory command (that is, CD, MD, or RD), only directories are used.

If you enclose the matching path in quotation marks, file and directory name completion correctly handles file names that contain spaces or special characters.

The following special characters require quotation marks: &

[] {} ^ =;!'+, `~ [space]

If the information provided contains spaces, use quotation marks to enclose the text (for example, computer name).

If you complete the operation by processing file and directory names from within String, any part of [Path] on the right side of the cursor (that is, the location in String where the operation is completed) is discarded.

The above are the startup parameters of cmd.exe, and the editor believes that there are some knowledge points that we may see or use in our daily work. I hope you can learn more from this article. For more details, please follow the industry information channel.

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