4.3BSD-Reno/share/man/cat2/sigprocmask.0

SIGPROCMASK(2)		      1990		   SIGPROCMASK(2)



NNAAMMEE
     sigprocmask - manipulate current signal mask

SSYYNNOOPPSSIISS
     ##iinncclluuddee <<ssiiggnnaall..hh>>

     ssiiggpprrooccmmaasskk((hhooww,, sseett,, oosseett));;
     iinntt hhooww;;
     ssiiggsseett__tt **sseett,, **oosseett;;

     mmaasskk == ssiiggmmaasskk((ssiiggnnuumm))

DDEESSCCRRIIPPTTIIOONN
     The _s_i_g_s_e_t_m_a_s_k function examines and/or the current signal
     mask (those signals that are blocked from delivery).  Sig-
     nals are blocked if they are members of the current signal
     mask set.

     If _s_e_t is not null, the action of _s_i_g_s_e_t_m_a_s_k depends on the
     value of the parameter _h_o_w.  The signal mask is changed as a
     function of the specified _s_e_t and the current mask.  The
     function is specified by _h_o_w using one of the following
     values from <signal.h>:

     SIG_BLOCK	  The new mask is the union of the current mask
		  and the specified _s_e_t.

     SIG_UNBLOCK  The new mask is the intersection of the current
		  mask and the complement of the specified _s_e_t.

     SIG_SETMASK  The current mask is replaced by the specified
		  _s_e_t.

     If _o_s_e_t is not null, the previous value of the signal mask.
     When _s_e_t is null, this provides a way to examine the signal
     mask without changing it.

     The system quietly disallows SIGKILL or SIGSTOP to be
     blocked.

RREETTUURRNN VVAALLUUEE
     A 0 value indicated that the call succeeded.  A -1 return
     value indicates an error occurred and _e_r_r_n_o is set to indi-
     cated the reason.

EERRRROORRSS
     The _s_i_g_p_r_o_c_m_a_s_k call will fail and the signal mask will be
     unchanged if one of the following occurs:

     [EINVAL]	    _h_o_w has a value other than those listed here.





Printed 7/27/90               July				1






SIGPROCMASK(2)		      1990		   SIGPROCMASK(2)



SSEEEE AALLSSOO
     kill(2), sigaction(2), sigsetops(2), sigsuspend(2)





















































Printed 7/27/90               July				2