Question

So I recently stumbled on the (potentially) useful %~$PATH:1 expansion, however I seem to be unable to make it work correctly. I tried to use it to make a cheap Windows version of the which command, however the syntax seems to be defeating me. My batch file looks like this:

@echo off
echo %~$PATH:1

However when I run this with for example

which cmd

all I get as output of “ECHO is off.”, which means according to the docs that the %~$PATH:1 didn’t find “cmd”. What am I doing wrong?

Answer 1

Checking for files with the extensions .exe, .cmd or .bat is not enough. The set of applicable extensions is defined in the environment variable PATHEXT.

Here is my version of a which command that honors the PATHEXT variable upon search:

@echo off
rem Windows equivalent of Unix which command

setlocal enabledelayedexpansion

if "%~1"=="" (
    echo Usage: which cmdname
    exit /b 1
)

call :findOnPath "%~1"
if not errorlevel 1 exit /b 0
for %%E in (%PATHEXT:;= %) do (
    call :findOnPath "%~1%%E"
    if not errorlevel 1 exit /b 0
)

echo "%~1" not found on PATH.
exit /b 1

:findOnPath
    if not "%~$PATH:1" == "" (
        echo "%~$PATH:1"
        exit /b 0
    )
    exit /b 1