NAME¶

syscall - indirect system call

SYNOPSIS¶

#define _GNU_SOURCE        /* or _BSD_SOURCE or _SVID_SOURCE */
#include <unistd.h>
#include <sys/syscall.h>   /* For SYS_xxx definitions */
int syscall(int number, ...);

DESCRIPTION¶

syscall() performs the system call whose assembly language interface has the specified number with the specified arguments. Symbolic constants for system calls can be found in the header file <sys/syscall.h>.

RETURN VALUE¶

The return value is defined by the system call being invoked. In general, a 0 return value indicates success. A -1 return value indicates an error, and an error code is stored in errno.

NOTES¶

syscall() first appeared in 4BSD.

EXAMPLE¶

#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/types.h>
int
main(int argc, char *argv[])
{


    pid_t tid;


    tid = syscall(SYS_gettid);
}

SEE ALSO¶

_syscall(2), intro(2), syscalls(2)

COLOPHON¶

This page is part of release 3.22 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.