.\"	$NetBSD: env.1,v 1.16 2024/10/28 11:30:37 kim Exp $
.\"
.\" Copyright (c) 1980, 1990 The Regents of the University of California.
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.\" the Institute of Electrical and Electronics Engineers, Inc.
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.\"	from: @(#)printenv.1	6.7 (Berkeley) 7/28/91
.\"	$NetBSD: env.1,v 1.16 2024/10/28 11:30:37 kim Exp $
.\"
.Dd October 28, 2024
.Dt ENV 1
.Os
.Sh NAME
.Nm env
.Nd set and print environment
.Sh SYNOPSIS
.Nm
.Op Fl 0i
.Op Fl C Ar dir
.Op Fl u Ar name
.Op Ar name=value ...
.Oo
.Ar utility
.Op argument ...
.Oc
.Sh DESCRIPTION
.Nm
executes
.Ar utility
after modifying the environment as
specified on the command line.
Each
.Ar name=value
option specifies
an environmental variable,
.Ar name  ,
with a value of
.Ar value  .
The
.Sq Fl i
option causes
.Nm
to completely ignore the environment
it inherits.
.Pp
The
.Sq Fl C Ar dir
option causes the working directory to be changed to
.Ar dir .
.Pp
The
.Sq Fl u Ar name
option causes removal of the
.Ar name
environment variable if it is in the environment.
This is similar to the
.Ic unset
command in
.Xr sh 1 .
The value for
.Ar name
must not include the
.Ql =
character.
.Pp
If no
.Ar utility
is specified,
.Nm
prints out the names and values of the variables in the environment.
Each
.Ar name=value
pair is separated by a new line unless
.Fl 0
is specified, in which case name/value pairs are separated by NUL.
The
.Fl 0
option and
.Ar utility
must not be specified together.
.Sh EXIT STATUS
.Nm
exits with one of the following values:
.Bl -tag -width Ds
.It 0
.Ar utility
was invoked and completed successfully.
In this case the exit code is returned by the utility itself, not
.Nm .
If no utility was specified, then
.Nm
completed successfully and returned the exit code itself.
.It 1
An invalid command line option was passed to
.Nm .
.It 1\-125
.Ar utility
was invoked, but failed in some way;
see its manual page for more information.
In this case the exit code is returned by the utility itself, not
.Nm .
.It 125
.Ar utility
was specified together with the
.Fl 0
option.
.It 126
.Ar utility
was found, but could not be invoked.
.It 127
.Ar utility
could not be found.
.El
.Sh COMPATIBILITY
The historic
.Fl
option has been deprecated but is still supported in this implementation.
.Pp
The
.Fl C , u
and
.Fl 0
options are non-standard extensions.
.Sh SEE ALSO
.Xr chdir 2 ,
.Xr execvp 3 ,
.Xr environ 7
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.2-92 .
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.4 .
.Pp
The
.Fl u
and
.Fl 0
options first appeared in
.Nx 10 .
.Pp
The
.Fl C
option first appeared in
.Nx 10.1 .
.Sh BUGS
.Nm
doesn't handle commands with equal
.Pq Dq =
signs in their
names, for obvious reasons.