.\" Copyright (c) 1983, 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)sigblock.2	6.8 (Berkeley) 07/28/92
.\"
.Dd 
.Dt SIGBLOCK 2
.Os BSD 4.2
.Sh NAME
.Nm sigblock
.Nd block signals
.Sh SYNOPSIS
.Fd #include <signal.h>
.Ft int
.Fn sigblock "int mask"
.Ft int
.Fn sigmask signum
.Sh DESCRIPTION
.Bf -symbolic
This interface is made obsolete by:
.Ef
.Xr sigprocmask 2 .
.Pp
.Fn Sigblock
adds the signals specified in
.Fa mask
to the set of signals currently
being blocked from delivery.
Signals are blocked if the
corresponding bit in 
.Fa mask
is a 1; the macro
.Fn sigmask
is provided to construct the mask for a given
.Fa signum .
.Pp
It is not possible to block
.Dv SIGKILL
or
.Dv SIGSTOP ;
this restriction is silently
imposed by the system.
.Sh RETURN VALUES
The previous set of masked signals is returned.
.Sh SEE ALSO
.Xr kill 2 ,
.Xr sigprocmask 2 ,
.Xr sigaction 2 ,
.Xr sigsetmask 2 ,
.Xr sigsetops 3
.Sh HISTORY
The
.Nm
function call appeared in
.Bx 4.2
and has been deprecated.