4.4BSD/usr/share/man/cat2/__syscall.0

SYSCALL(2)                  BSD Programmer's Manual                 SYSCALL(2)

NNAAMMEE
     ssyyssccaallll, ____ssyyssccaallll - indirect system call

SSYYNNOOPPSSIISS
     ##iinncclluuddee <<ssyyss//ssyyssccaallll..hh>>
     ##iinncclluuddee <<uunniissttdd..hh>>

     _i_n_t
     ssyyssccaallll(_i_n_t _n_u_m_b_e_r, _._._.);

     _i_n_t
     ____ssyyssccaallll(_q_u_a_d___t _n_u_m_b_e_r, _._._.);

DDEESSCCRRIIPPTTIIOONN
     SSyyssccaallll() performs the system call whose assembly language interface has
     the specified _n_u_m_b_e_r with the specified arguments.  Symbolic constants
     for system calls can be found in the header file <_s_y_s_/_s_y_s_c_a_l_l_._h>. The
     ____ssyyssccaallll form should be used when one or more of the parameters is a
     64-bit argument to ensure that argument alignment is correct.  This sys-
     tem call is useful for testing new system calls that do not have entries
     in the C library.

RREETTUURRNN VVAALLUUEESS
     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 _e_r_r_n_o.

BBUUGGSS
     There is no way to simulate system calls that have multiple return values
     such as pipe(2).

HHIISSTTOORRYY
     The ssyyssccaallll function call appeared in 4.0BSD.

4th Berkeley Distribution        June 16, 1993                               1