substring using bat command

Question

Hi all,

I have the following thing in my bat file. say

set path=c:\temp\test

so basically i want to have an output which would give me the result as c:\temp\

i didnt find any indexof equivalent in bat command.

Thanks.

Answer 1

A question that really makes me wish 4DOS still existed. However, I found something that might help in alt.msdos.batch.nt. The manual page for set seems to contain most of the same information. (command help set)

set test=123456789

rem extract chars 0-5 from the variable test
set test=%test:~0,5%

echo %test%

(Note: tested on Windows XP SP3)

Answer 2

Naïve substrings have the problem that you have to adjust them every time your paths change and it isn't a generic solution to the problem.

The following batch file gives a proof of concept how you might do the truncation part of the path:

@echo off
set foo=C:\Temp\Test
call :strip
echo %foo%
goto :eof

:strip
if not "%foo:~-1%"=="\" (
    set foo=%foo:~0,-1%
    goto :strip
)
goto :eof

It's hard-coded to a single variable but that is easily fixed if needed.

The core part here is the strip subroutine which loops and cuts off the last character of the string until a backslash is found. This effectively removes the last part of the path.

Answer 3

Why do you want that?

Johannes' answer is a possible solution, but maybe the path you refer to is being (or could be) passed as an argument to the script, in which case you can use the following syntax:

REM Extracts the drive and path from argument %1
SET p=%~dp1

Alternatively you may combine .. and the script path (%0):

REM Sets p to a sibling of the script directory
SET p=%~dp0..\test