initgroups - initialize the supplementary group id's from /etc/group
int initgroups(char *name, gid_t basegid)
Initgroups() is used by programs like login(1), or su(1) to set the
supplementery group id's for the user they are changing into. The
routine is called with the login name and the group id of the user as
found in the password file. Initgroups will then scan the group file for
name in the group member list of each group. A group the user is a
member of will be added to the supplementary group id set. The group id
basegid is also added to this set.
Initgroups returns the return value of the setgroups(2) call.
Kees J. Bot (email@example.com)