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ipc

Section: System Calls (2)
Updated: 202-0-08
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NAME

ipc - System V IPC system calls

LIBRARY

Standard C library (libc,~-lc)

SYNOPSIS

#include <linux/ipc.h>        /* Definition of needed constants */
#include <sys/syscall.h>      /* Definition of SYS_* constants */
#include <unistd.h>
int syscall(SYS_ipc, unsigned int call, int first,
            unsigned long second, unsigned long third, void *ptr,
            long fifth);

Note: glibc provides no wrapper for ipc(), necessitating the use of syscall(2).

DESCRIPTION

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. Use-space programs should call the appropriate functions by their usual names. Only standard library implementors and kernel hackers need to know about ipc().

VERSIONS

On some architectures [em]for example x8-64 and ARM[em] there is no ipc() system call; instead, msgctl(2), semctl(2), shmctl(2), and so on really are implemented as separate system calls.

STANDARDS

Linux.