SYSCALL(2)                                                          SYSCALL(2)



NAME
       syscall - indirect system call

SYNOPSIS
       #include <syscall.h>

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

DESCRIPTION
       _S_y_s_c_a_l_l  performs the system call whose assembly language interface has
       the specified _n_u_m_b_e_r_, register arguments _r_0 and _r_1  and  further  argu‐
       ments  _a_r_g.   Symbolic  constants  for system calls can be found in the
       header file _<_s_y_s_c_a_l_l_._h_>_.

       The r0 value of the system call is returned.

DIAGNOSTICS
       When the C-bit is set, _s_y_s_c_a_l_l returns -1 and sets the  external  vari‐
       able _e_r_r_n_o (see _i_n_t_r_o(2)).

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



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