syscall

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

syscalls(2)