setresgid(2) on Linux
The text 764692235ae7, as Debian 2.1 (Slink), Debian 2.0 (Hamm) shipped it.
set real, effective and saved user or group ID
The text 764692235ae7, as Debian 2.1 (Slink), Debian 2.0 (Hamm) shipped it.
set real, effective and saved user or group ID