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windowsbatch-filefindstr

Windows Cmd findstr - Regex with digits not working

I'm trying to validate if the IP address argument passed to a batch file is valid or not. Unfortunately, Windows findstr is not reliably working though the regex fed into is matched.

Following is the summary of all the results.

findstr sets errorlevel to 0 if there is a match, 1 if there is no match.

C:\iSTEP\VMTicketing\RealVNC>echo 192.10.10.10 | findstr /R "[0-2][0-9][0-9]\.[0-2][0-9][0-9]\.[0-2][0-9][0-9]\.[0-2][0-9][0-9]"

C:\iSTEP\VMTicketing\RealVNC>echo %errorlevel%
1

C:\iSTEP\VMTicketing\RealVNC>echo 192.101.101.101 | findstr /R "[0-2][0-9][0-9]\.[0-2][0-9][0-9]\.[0-2][0-9][0-9]\.[0-2][0-9][0-9]"
192.101.101.101

C:\iSTEP\VMTicketing\RealVNC>echo %errorlevel%
0

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /R "[0-2][0-9][0-9]?\.[0-2]?[0-9][0-9]?\.[0-2]?[0-9][0-9]?\.[0-2]?[0-9][0-9]?"

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /R "[0-2]?[0-9][0-9]?\.[0-2]?[0-9][0-9]?\.[0-2]?[0-9][0-9]?\.[0-2]?[0-9][0-9]?"

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /R "\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"

C:\iSTEP\VMTicketing\RealVNC>echo %errorlevel%
1

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /b /e /R "\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"

C:\iSTEP\VMTicketing\RealVNC>echo %errorlevel%
1

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /b /e /R "\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b"

C:\iSTEP\VMTicketing\RealVNC>echo %errorlevel%
1

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /b /e /R "\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"

C:\iSTEP\VMTicketing\RealVNC>echo %errorlevel%
1

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /b /e /R "*\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}*"
FINDSTR: No search strings

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /b /e /R "*\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"
FINDSTR: No search strings

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /b /e /R "\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}*"

C:\iSTEP\VMTicketing\RealVNC>echo %errorlevel%
1

C:\iSTEP\VMTicketing\RealVNC>echo 1.1.1.1 | findstr /b /e /R "\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\>"

C:\iSTEP\VMTicketing\RealVNC>echo %errorlevel%
1

Commandoutput

Solution

  • A simple way of performing matches using powershell regex:

    @Echo off
 Call :Regex "131.21.1.101" "\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"
 Echo(%Errorlevel%
 Call :Regex "1321.101" "\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"
 Echo(%Errorlevel%
Goto :Eof

:Regex
 powershell.exe -noprofile -c "'%~1' -match '%~2'" | findstr /l "True" > nul || Exit /b 1
Exit /b 0

    For details on powershell regex syntax see here