which

This tool locates executable files on the PATH. And it does a lot more. It can be used to determine which executable Windows will call, when multiple copies exist.

Usage

C:\...\>which.exe /?
which - Version 4.0
Freeware written by Gerson Kurz (http://p-nand-q.com)

USAGE: which.EXE [OPTIONS] FILE {FILE}.
OPTIONS:
    /EXTENSION: search for extension , can be a ; separated list
          /DIR: add directory , can be a ; separated list
    /RECURSIVE: search directories recursively
       /SINGLE: stop after the first find result
          /ENV: environment variable, defaults to PATH
   FILE {FILE}: one or more files to find

Examples

To find notepad on the path, try:

C:\...\>which notepad
which - Version 4.0
Freeware written by Gerson Kurz (http://p-nand-q.com)

C:\Windows\notepad.exe [22.08.2013 13:00:12, 217600 bytes]
C:\Windows\SysWOW64\notepad.exe [22.08.2013 05:35:48, 208896 bytes]
C:\Windows\system32\notepad.exe [22.08.2013 13:00:12, 217600 bytes]

Note: You can see from this that on a x64 system, which will show you both 32-bit and 64-bit variants if possible.

Developers will love that which also knows about the environment variables INCLUDE and LIBS. For example, try this:

C:\...\>which windows.h
which - Version 4.0
Freeware written by Gerson Kurz (http://p-nand-q.com)

C:\Program Files (x86)\Windows Kits\8.0\include\um\Windows.h [02.08.2013 17:56:14, 6630 bytes]

You can also use which to list all DLLs starting with "TA" on your path:

C:\...\>which ta*.dll
which - Version 4.0
Freeware written by Gerson Kurz (http://p-nand-q.com)

C:\Windows\SysWOW64\tapi3.dll [22.08.2013 05:46:31, 846336 bytes]
C:\Windows\SysWOW64\tapi32.dll [22.08.2013 05:42:27, 196608 bytes]
C:\Windows\SysWOW64\TapiMigPlugin.dll [22.08.2013 05:38:33, 44032 bytes]
C:\Windows\SysWOW64\tapiperf.dll [22.08.2013 06:04:40, 10240 bytes]
C:\Windows\SysWOW64\tapisrv.dll [22.08.2013 05:33:38, 248320 bytes]
... (lots more omitted here)

Download

License

which is freeware, BSD-licensed.

History

GK, Feb 16, 2014