freebsd-skq/usr.bin/which/which.1
fernape dab47decb2 Fix typo and environment variable macro
Follow up for r366119

Reported by:	xtouqh@mm.st
Differential Revision:	https://reviews.freebsd.org/D26182
2020-09-24 16:42:17 +00:00

128 lines
3.5 KiB
Groff

.\" Manpage Copyright (c) 1995, Jordan Hubbard <jkh@FreeBSD.org>
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.\" $FreeBSD$
.\"
.Dd September 24, 2020
.Dt WHICH 1
.Os
.Sh NAME
.Nm which
.Nd "locate a program file in the user's path"
.Sh SYNOPSIS
.Nm
.Op Fl as
.Ar program ...
.Sh DESCRIPTION
The
.Nm
utility
takes a list of command names and searches the path for each executable
file that would be run had these commands actually been invoked.
.Pp
The following options are available:
.Bl -tag -width indent
.It Fl a
List all instances of executables found (instead of just the first one
of each).
.It Fl s
No output, just return 0 if all of the executables are found, or 1 if
some were not found.
.El
.Pp
Some shells may provide a builtin
.Nm
command which is similar or identical to this utility.
Consult the
.Xr builtin 1
manual page.
.Sh EXAMPLES
Locate the
.Xr ls 1
and
.Xr cp 1
commands:
.Bd -literal -offset indent
$ /usr/bin/which ls cp
/bin/ls
/bin/cp
.Ed
.Pp
Same as above with a specific
.Ev PATH
and showing all occurrences:
.Bd -literal -offset indent
$ PATH=/bin:/rescue /usr/bin/which -a ls cp
/bin/ls
/rescue/ls
/bin/cp
/rescue/cp
.Ed
.Pp
.Nm which
will show duplicates if the same executable is found more than once:
.Bd -literal -offset indent
$ PATH=/bin:/bin /usr/bin/which -a ls
/bin/ls
/bin/ls
.Ed
.Pp
Do not show output.
Just exit with an appropriate return code:
.Bd -literal -offset indent
$ /usr/bin/which -s ls cp
$ echo $?
0
$ /usr/bin/which -s fakecommand
$ echo $?
1
.Ed
.Sh SEE ALSO
.Xr builtin 1 ,
.Xr csh 1 ,
.Xr find 1 ,
.Xr locate 1 ,
.Xr whereis 1
.Sh HISTORY
The
.Nm
command first appeared in
.Fx 2.1 .
.Sh AUTHORS
.An -nosplit
The
.Nm
utility was originally written in Perl and was contributed by
.An Wolfram Schneider Aq Mt wosch@FreeBSD.org .
The current version of
.Nm
was rewritten in C by
.An Daniel Papasian Aq Mt dpapasia@andrew.cmu.edu .