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.\" @(#)setregid.2 8.2 (Berkeley) 4/16/94
.Nd set real and effective group ID
.Fn setregid "gid_t rgid" "gid_t egid"
The real and effective group ID's of the current process
are set to the arguments.
Unprivileged users may change the real group
ID to the effective group ID and vice-versa; only the super-user may
Supplying a value of -1 for either the real or effective
group ID forces the system to substitute the current
ID in place of the -1 parameter.
function was intended to allow swapping
the real and effective group IDs
in set-group-ID programs to temporarily relinquish the set-group-ID value.
This function did not work correctly,
and its purpose is now better served by the use of the
When setting the real and effective group IDs to the same value,
Upon successful completion, a value of 0 is returned. Otherwise,
a value of -1 is returned and
is set to indicate the error.
The current process is not the super-user and a change
other than changing the effective group-id to the real group-id
function call appeared in