semget
See the current Perl documentation for semget.
Here is our local, out-dated (pre-5.6) version:

semget - get set of SysV semaphores

semget KEY,NSEMS,FLAGS

Calls the System
V
IPC function semget. Returns the semaphore id, or the undefined value if there is an error. See also
IPC::SysV
and
IPC::SysV::Semaphore
documentation.