Manpages - sg.1
NAME
sg - execute command as different group ID
SYNOPSIS
sg [-] [group [-c ] command]
DESCRIPTION
The sg command works similar to newgrp but accepts a command. The command will be executed with the /bin/sh shell. With most shells you may run sg from, you need to enclose multi-word commands in quotes. Another difference between newgrp and sg is that some shells treat newgrp specially, replacing themselves with a new instance of a shell that newgrp creates. This doesnt happen with sg, so upon exit from a sg command you are returned to your previous group ID.
CONFIGURATION
The following configuration variables in /etc/login.defs change the behavior of this tool:
SYSLOG_SG_ENAB (boolean)
Enable "syslog" logging of sg activity.
FILES
/etc/passwd
User account information.
/etc/shadow
Secure user account information.
/etc/group
Group account information.
/etc/gshadow
Secure group account information.
SEE ALSO
*id*(1), *login*(1), *newgrp*(1), *su*(1), *gpasswd*(1), *group*(5), *gshadow*(5).