4.3BSD - /usr/man/cat2/syscall.0

SYSCALL(2)                                                          SYSCALL(2)


NAME
       syscall - indirect system call

SYNOPSIS
       #include <syscall.h>

       syscall(number, arg, ...)  (VAX-11)

DESCRIPTION
       Syscall  performs the system call whose assembly language interface has
       the specified number, register arguments r0 and r1  and  further  argu‐
       ments  arg.   Symbolic  constants  for system calls can be found in the
       header file <syscall.h>.

       The r0 value of the system call is returned.

DIAGNOSTICS
       When the C-bit is set, syscall returns -1 and sets the  external  vari‐
       able errno (see intro(2)).

BUGS
       There  is no way to simulate system calls such as pipe(2), which return
       values in register r1.


4th Berkeley Distribution       April 16, 1986                      SYSCALL(2)