.\"	$OpenBSD: which.1,v 1.20 2010/09/03 11:09:29 jmc Exp $
.\"
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.\"     from: @(#)which.1	6.3 (Berkeley) 4/23/91
.\"
.Dd $Mdocdate: September 3 2010 $
.Dt WHICH 1
.Os
.Sh NAME
.Nm which
.Nd "locate a program file (or files) in the path"
.Sh SYNOPSIS
.Nm which
.Op Fl a
.Ar name ...
.Sh DESCRIPTION
.Nm
takes a list of names and looks for the files which would be
executed had these names been given as commands.
Each argument is searched for along the user's path.
.Pp
If the
.Fl a
flag is given,
.Nm
will return a list of all matches instead of just the first match.
.Sh ENVIRONMENT
The following environment variables affect the execution of
.Nm which :
.Bl -tag -width PATH
.It Ev PATH
A colon-separated list of directories in which to find executables.
If
.Ev PATH
is not set, and the given name is not a fully qualified
or relative pathname,
.Nm
will fail.
.El
.Sh EXIT STATUS
The
.Nm
utility exits with one of the following values:
.Pp
.Bl -tag -width Ds -offset indent -compact
.It 0
All names were successfully resolved.
.It 1
Some names were resolved but not all.
.It 2
No names were resolved.
.It \-1
A system error occurred.
.El
.Sh DIAGNOSTICS
A diagnostic is given if an executable file with the argument
name was not found in the path.
.Sh SEE ALSO
.Xr csh 1 ,
.Xr find 1 ,
.Xr locate 1 ,
.Xr whereis 1 ,
.Xr environ 7
.Sh STANDARDS
.Nm
also exists as a built-in to
.Xr csh 1 ,
though with a different syntax.
.Sh HISTORY
A
.Nm
command appeared in
.Bx 3.0 .