.\" Copyright 1991, Julianne Frances Haugh
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of Julianne F. Haugh nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"	$Id: newgrp.1,v 1.6 2000/08/26 18:27:17 marekm Exp $
.\"
.TH NEWGRP 1
.SH NAME
newgrp \- Change group ID
.br
sg \- Execute command as different group ID
.SH SYNOPSIS
.BR newgrp " [" - ]
[\fIgroup\fR]
.br
.BR sg " [" - ]
[\fIgroup\fR [[\fB-c\fR] \fIcommand\fR]]
.SH DESCRIPTION
.B newgrp
is used to change the current group ID during a login session.
If the optional \fB\-\fR flag is given, the user's environment
will be reinitialized as though the user had logged in, otherwise
the current environment, including current working directory,
remains unchanged.
.PP
.B newgrp
changes the current real group ID to the named group, or to
the default group listed in \fI/etc/passwd\fR if no group name
is given.
The user will be prompted for a password if they do not have a
password and the group does, or if the user is not listed as a
member and the group has a password.
The user will be denied access if the group password is empty
and the user is not listed as a member.
.PP
The
.B sg
command works similiar to \fBnewgrp\fR but does not replace the
user's shell, so upon exit from a \fBsg\fR command, you are
returned to your previous group ID.
.B sg
also accepts a command.
The command will be executed with the Bourne shell and must be
enclosed in quotes.
.SH CAVEATS
This version of \fBnewgrp\fR has many compilation options,
only some of which may be in use at any particular site.
.SH FILES
/etc/passwd \- user account information
.br
/etc/group \- group information
.SH SEE ALSO
.BR login (1),
.BR id (1),
.BR su (1)
.SH AUTHOR
Julianne Frances Haugh (jfh@austin.ibm.com)