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$FreeBSD: releng/10.3/usr.bin/newgrp/newgrp.1 246553 2013-02-08 14:14:00Z des $
.Dd February 8, 2013 .Dt NEWGRP 1 .Os .Sh NAME .Nm newgrp .Nd change to a new group .Sh SYNOPSIS .Nm .Op Fl l .Op Ar group .Sh DESCRIPTION The .Nm utility creates a new shell execution environment with modified real and effective group IDs.
p The options are as follows: l -tag -width indent t Fl l Simulate a full login. The environment and umask are set to what would be expected if the user actually logged in again. .El
p If the .Ar group operand is present, a new shell is started with the specified effective and real group IDs. The user will be prompted for a password if they are not a member of the specified group.
p Otherwise, the real, effective and supplementary group IDs are restored to those from the current user's password database entry. .Sh EXIT STATUS The .Nm utility attempts to start the shell regardless of whether group IDs were successfully changed.
p If an error occurs and the shell cannot be started, .Nm exits >0. Otherwise, the exit status of .Nm is the exit status of the shell. .Sh SEE ALSO .Xr csh 1 , .Xr groups 1 , .Xr login 1 , .Xr sh 1 , .Xr su 1 , .Xr umask 1 , .Xr group 5 , .Xr passwd 5 , .Xr environ 7 .Sh STANDARDS The .Nm utility conforms to .St -p1003.1-2001 . .Sh HISTORY A .Nm utility appeared in .At v6 . .Sh BUGS For security reasons, the .Nm utility is normally installed without the setuid bit. To enable it, run the following command: d -literal -offset indent chmod u+s /usr/bin/newgrp .Ed
p Group passwords are inherently insecure as there is no way to stop users obtaining the password hash from the group database. Their use is discouraged. Instead, users should simply be added to the necessary groups.