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which
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Description
La commande which est une commande assez classique des systèmes Unix. Elle permet de retrouver l’emplacement d’un exécutable. Elle ne sert donc que dans des cas spécifique mais il est important de connaître cette commande.
Exemple
root@solaris:~# which prtdiag /usr/sbin/prtdiag axel@solaris:~$ which df /usr/gnu/bin/df
Man solaris de la commande which
User Commands 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 executed when this argument had been entered
at the shell prompt. It does this by searching for an exe-
cutable or script in the directories listed in the environ-
ment 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 function for which itself. For exam-
ple:
which() { declare -f | which --read-functions $@ }
export -f which
--skip-functions
Ignore option `--read-functions', if any. This is useful
to explicity 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.
SunOS 5.10 Last change: 1
User Commands WHICH(1)
--show-dot
If a directory in PATH starts with a dot and a matching
executable was found for that path, then print "./pro-
gramname" rather than the full path.
--show-tilde
Output a tilde when a directory matches the HOME direc-
tory. 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
successfully.
--help
Print usage information on standard output then exit
successfully.
RETURN VALUE
Which returns the number of failed arguments, or -1 when no
`programname' 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
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User Commands WHICH(1)
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 direc-
tories to be different when one of them contains a path with
a symbolic link.
AUTHOR
Carlo Wood <carlo@gnu.org>
SEE ALSO
bash(1)
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
_______________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE|
|____________________|_________________|
| Availability | shell/which |
|____________________|_________________|
| Interface Stability| Uncommitted |
|____________________|_________________|
NOTES
Source for GNU which is available on http://opensolaris.org.
SunOS 5.10 Last change: 3