ipc - System V IPC system calls
int ipc(unsigned int call, int first, int second, int third,
void *ptr, long fifth);
ipc() is a common kernel entry point for the System V IPC calls for messages, semaphores, and shared memory. call determines which IPC function to invoke; the other arguments are passed through to the appropriate call.
User-space programs should call the appropriate functions by their usual names. Only standard library implementors and kernel hackers need to know about ipc().
ipc() is Linux-specific, and should not be used in programs intended to be portable.
On some architectures—for example x86-64 and ARM—there is no ipc() system call; instead, msgctl(2), semctl(2), shmctl(2), and so on really are implemented as separate system calls.
msgctl(2), msgget(2), msgrcv(2), msgsnd(2), semctl(2), semget(2), semop(2), semtimedop(2), shmat(2), shmctl(2), shmdt(2), shmget(2), svipc(7)