WHICH command for DOS

@echo off
SETLOCAL
(set WF=)

:: Look for file in the current directory

for %%a in ("" %!!%) do (
if not defined WF if exist "%~1%%~a" set WF=%CD%\%~1%%~a)

:: Look for file in the PATH

for %%a in ("" %!!%) do (
if not defined WF for %%g in ("%~1%%~a") do (
if exist "%%~$PATH:g" set WF=%%~$PATH:g))

:: Store the Help Error message

if NOT "%~x1"=="" goto:END
for /f "delims=." %%a in ('help.exe *') do set HlpErr=%%a

:: If command missing from Help, goto end

help.exe "%~1" |find "%HlpErr%">nul && goto:END

:: Listed in help so find file in System32

for %%a in (exe com) do (
if /i "%WF%"=="%windir%\system32\%~1.%%a" goto:END)

:: File not in System32, so must be an internal command

set WF="%~1" is an internal command

:END
if defined WF (echo.%WF%) else (
echo The file: "%~1" was not found)

:: Credits:
:: Clay Calvert
:: alt.msdos.batch.nt