SYSCALL(2) BSD System Calls Manual SYSCALL(2)NAME
syscall — indirect system call
SYNOPSIS
#include <sys/syscall.h>
#include <unistd.h>
int
syscall(int number, ...);
DESCRIPTIONSyscall() 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⟩. This
function is useful for testing new system calls that do not have entries
in the C library.
RETURN VALUES
The return values are defined by the system call being invoked. In gen‐
eral, a 0 return value indicates success. A -1 return value indicates an
error, and an error code is stored in errno.
BUGS
There is no way to simulate system calls that have multiple return values
such as pipe(2).
HISTORY
The syscall() function call appeared in 4.0BSD.
4th Berkeley Distribution June 23, 2008 4th Berkeley Distribution