WHICH(1)

WHICH(1)                                  WHICH(1)



NAME
       which - shows the full path of (shell) commands.

SYNOPSIS
       which [options] [--] programname [...]

DESCRIPTION
       Which takes one or more arguments. For each of its arguments it prints
       to stdout the full path of the executables that would have been exe-
       cuted when this argument had been entered at the shell prompt. It does
       this by searching for an executable or script in the directories listed
       in the environment variable PATH using the same algorithm as bash(1).

       This man page is generated from the file which.texinfo.

OPTIONS
       --all, -a
       Print all matching executables in PATH, not just the first.

       --read-alias, -i
       Read aliases from stdin, reporting matching ones on stdout. This is
       useful in combination with using an alias for which itself. For
       example
       alias which=´alias | which -i´.

       --skip-alias
       Ignore option `--read-alias´, if any. This is useful to explicity
       search for normal binaries, while using the `--read-alias´ option
       in an alias or function for which.

       --read-functions
       Read shell function definitions from stdin, reporting matching ones
       on stdout. This is useful in combination with using a shell func-
       tion for which itself.  For example:
       which() { declare -f | which --read-functions $@ }
       export -f which

       --skip-functions
       Ignore option `--read-functions´, if any. This is useful to explic-
       ity search for normal binaries, while using the `--read-functions´
       option in an alias or function for which.

       --skip-dot
       Skip directories in PATH that start with a dot.

       --skip-tilde
       Skip directories in PATH that start with a tilde and executables
       which reside in the HOME directory.

       --show-dot
       If a directory in PATH starts with a dot and a matching executable
       was found for that path, then print "./programname" rather than the
       full path.

       --show-tilde
       Output a tilde when a directory matches the HOME directory. This
       option is ignored when which is invoked as root.

       --tty-only
       Stop processing options on the right if not on tty.

       --version,-v,-V
       Print version information on standard output then exit success-
       fully.

       --help
       Print usage information on standard output then exit successfully.

RETURN VALUE
       Which returns the number of failed arguments, or -1 when no `program-
       name´ was given.

EXAMPLE
       The recommended way to use this utility is by adding an alias (C shell)
       or shell function (Bourne shell) for which like the following:

       [ba]sh:

        which ()
        {
          (alias; declare -f) | /usr/bin/which --tty-only --read-alias --read-functions --show-tilde --show-dot $@
        }
        export -f which

       [t]csh:

        alias which ´alias | /usr/bin/which --tty-only --read-alias --show-dot --show-tilde´

       This  will  print  the readable ~/ and ./ when starting which from your
       prompt, while still printing the full path when used from a script:

        > which q2
        ~/bin/q2
        > echo `which q2`
        /home/carlo/bin/q2


BUGS
       The HOME directory is determined by looking for    the  HOME  environment
       variable,  which     aborts     when this variable doesn´t exist.  Which will
       consider two equivalent directories to be different when     one  of  them
       contains a path with a symbolic link.

AUTHOR
       Carlo Wood <[email protected]>

SEE ALSO
       bash(1)



                                      WHICH(1)