/usr.bin/newgrp/newgrp.1

 1.\" Copyright (c) 2002 Tim J. Robbins.
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25.\" $FreeBSD$
26.\"
27.Dd May 23, 2002
28.Dt NEWGRP 1
29.Os
30.Sh NAME
31.Nm newgrp
32.Nd change to a new group
33.Sh SYNOPSIS
34.Nm
35.Op Fl l
36.Op Ar group
37.Sh DESCRIPTION
38The
39.Nm
40utility creates a new shell execution environment with modified
41real and effective group IDs.
42.Pp
43The options are as follows:
44.Bl -tag -width indent
45.It Fl l
46Simulate a full login.
47The environment and umask are set to what would be expected if the user
48actually logged in again.
49.El
50.Pp
51If the
52.Ar group
53operand is present, a new shell is started with the specified effective
54and real group IDs.
55The user will be prompted for a password if they are not a member of the
56specified group.
57.Pp
58Otherwise, the real, effective and supplementary group IDs are restored to
59those from the current user's password database entry.
60.Sh EXIT STATUS
61The
62.Nm
63utility attempts to start the shell regardless of whether group IDs
64were successfully changed.
65.Pp
66If an error occurs and the shell cannot be started,
67.Nm
68exits >0.
69Otherwise, the exit status of
70.Nm
71is the exit status of the shell.
72.Sh SEE ALSO
73.Xr csh 1 ,
74.Xr groups 1 ,
75.Xr login 1 ,
76.Xr sh 1 ,
77.Xr su 1 ,
78.Xr umask 1 ,
79.Xr group 5 ,
80.Xr passwd 5 ,
81.Xr environ 7
82.Sh STANDARDS
83The
84.Nm
85utility conforms to
86.St -p1003.1-2001 .
87.Sh HISTORY
88A
89.Nm
90utility appeared in
91.At v6 .
92.Sh BUGS
93Group passwords are inherently insecure as there is no way to stop
94users obtaining the crypted passwords from the group database.
95Their use is discouraged.