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Copyright © 2003-2013 by Prof. Timo Salmi  
Last modified Thu 14-Feb-2013 17:55:12

 
Assorted NT/2000/XP/.. CMD.EXE Script Tricks
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This page is edited from the 1cmdfaq.txt faq-file contained in my tscmd.zip command line interface (CLI) collection. That zipped file has much additional material, including a number of detached .cmd script files. It is recommended that you also get the zipped version as a companion.

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179} How to replace an asterisk "*" in an environment variable?

Replacing a standard character in a command-line script is straight-forward:
  @echo off & setlocal enableextensions
  set var=This is a string
  echo %var%
  echo %var: =-%
  endlocal & goto :EOF

The output will be:
  C:\TEST>CMDFAQ
  This is a string
  This-is-a-string

However, the following will not work as one would expect
  @echo off & setlocal enableextensions
  set var=This*is*a*string
  echo %var%
  echo %var:*=_%
  endlocal & goto :EOF

Adding a backslash or some other character would work
  @echo off & setlocal enableextensions
  set var=This\*is\*a\*string
  echo %var%
  echo %var:\*=-%
  endlocal & goto :EOF

The output will be:
  C:\TEST>CMDFAQ
  This\*is\*a\*string
  This-is-a-string

A Visual Basic Script (VBScript) aided command line script solution can be used without the complications
  @echo off & setlocal enableextensions
  set var=This*is*a*string
  echo %var%
  >"%temp%\tmp$$$.vbs" echo WScript.Echo Replace("%var%","*","-")
  for /f "delims=" %%a in ('
    cscript //nologo "%temp%\tmp$$$.vbs"') do set varNew=%%a
  for %%f in ("%temp%\tmp$$$.vbs") do if exist %%f del %%f
  echo %varNew%
  endlocal & goto :EOF

The output will be:
  C:\TEST>CMDFAQ
  This*is*a*string
  This-is-a-string

The following, limited pure script solution is possible. The solution is not generic, since one has to know in advance the number of asterisk occurrences in the string.
  @echo off & setlocal enableextensions
  set var=This*is*a*string
  for /f "tokens=1-4 delims=*" %%a in (
    "%var%") do set varNew=%%a-%%b-%%c-%%d
  echo %var%
  echo %varNew%
  endlocal & goto :EOF

The output will be:
  C:\TEST>CMDFAQ
  This*is*a*string
  This-is-a-string
The following version, also based on an alt.msdos.batch.nt discussion, is more generic, but not infallible (try with: set var=This**is**a**string)
  @echo off & setlocal enableextensions
  set var=This*is*a*string
  echo %var%
  :_loop
  for /f "tokens=1,* delims=*" %%a in (
    "%var%") do set var=%%a-%%b
  if not "%var%"=="%var:**=%" goto :_loop
  echo %var%
  endlocal & goto :EOF

References/Comments:
  Google Groups Nov 23 2009 - a long discussion