sigblock.2

<B>Digital的Unix操作系统VAX 4.2源码</B>

.\" SCCSID: @(#)sigblock.2	8.1	9/11/90
.TH sigblock 2
.SH Name
sigblock \- block signals
.SH Syntax
.nf
.B sigblock(\fImask\fP)
.B int \fImask\fP;
.SH Description
.NXR "sigblock system call"
.NXR "signal" "blocking"
The
.PN sigblock
system call
causes the signals specified in
.I mask
to be added to the set of signals currently
being blocked from delivery.  Signal
.I i
is blocked if the
.IR i th
bit in 
.I mask
is a 1.
.PP
It is not possible to block SIGKILL or SIGSTOP.
This restriction is silently
imposed by the system.
.PP
The previous set of masked signals is returned.
.SH See Also
kill(2), sigsetmask(2), sigvec(2)