The following table lists valid hexadecimal digits that you can use as the values for <B> and <F>:

• Using multiple commands
  
  To use multiple commands for <String>, separate them by the command separator && and enclose them in quotation marks. For example:
  
  

  "<Command>&&<Command>&&<Command>"
  

• Processing quotation marks
  
  If you specify /c or /k, cmd processes the remainder of String, and quotation marks are preserved only if all of the following conditions are met:
  
  
  • You do not use /s.
    
    
  • You use exactly one set of quotation marks.
    
    
  • You do not use any special characters within the quotation marks (for example: & < > ( ) @ ^ | ).
    
    
  • You use one or more white-space characters within the quotation marks.
    
    
  • The String within quotation marks is the name of an executable file.
    
    
  If the previous conditions are not met, String is processed by examining the first character to verify whether it is an opening quotation mark. If the first character is an opening quotation mark, it is stripped along with the closing quotation mark. Any text following the closing quotation marks is preserved.
  
  
• Executing registry subkeys
  
  If you do not specify /d 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 registry subkeys are present, they are executed before all other variables.
  
  

	Caution
	Incorrectly editing the registry may severely damage your system. Before making changes to the registry, you should back up any valued data on the computer.

• Enabling and disabling command extensions
  
  Command extensions are enabled by default in Windows XP. You can disable them for a particular process by using /e:off. You can enable or disable extensions for all cmd command-line options on a computer or 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
  
  Set the REG_DWORD value to either 0×1 (enabled) or 0×0 (disabled) in the registry by using Regedit.exe. User-specified settings take precedence over computer settings, and command-line options take precedence over registry settings.
  
  Caution   Incorrectly editing the registry may severely damage your system. Before making changes to the registry, you should back up any valued data on the computer.
  
  When you enable command extensions, 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 changes to external command processes)
    
    
• Enabling delayed environment variable expansion
  
  If you enable delayed environment variable expansion, you can use the exclamation point character to substitute the value of an environment variable at run time.
  
  
• Enabling file and directory name completion
  
  File and directory name completion is not enabled by default. You can enable or disable file name completion for a particular process of the cmd command with /f:{on|off}. You can enable or disable file and directory name completion for all processes of the cmd command on a computer or for a user logon 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 a control character for a particular function (for example, 0×9 is TAB and 0×08 is BACKSPACE). User-specified settings take precedence over computer settings, and command-line options take precedence over registry settings.
  
  

	Caution
	Incorrectly editing the registry may severely damage your system. Before making changes to the registry, you should back up any valued data on the computer.

If you enable file and directory name completion by using /f:on, use CTRL+D for directory name completion and CTRL+F for file name completion. To disable a particular completion character in the registry, use the value for white space [0×20] because it is not a valid control character.

If you process file and directory name completion from within String, any part of the Path to the right of the cursor is discarded (at the point in String where the completion was processed).