sigblock(2)

sigblock2

Block signals

Usage

#include <signal.h>

int

sigblock(int mask);

int

sigmask(signum);

Library

Standard C Library (libc, -lc)

Overview

This interface is made obsolete by sigprocmask(2).

Sigblock() adds the signals specified in mask to the set of signals currently being blocked from delivery. Signals are blocked if the corresponding bit in mask is a 1; the macro sigmask() is provided to construct the mask for a given signum.

It is not possible to block SIGKILL or SIGSTOP; this restriction is silently imposed by the system.

Return values

The previous set of masked signals is returned.

Releases

Unchanged in 155 releases since Mac OS X 10.2.

  1. 10.2–26.5

History

The sigblock() function call appeared in 4.2BSD and has been deprecated.

From Libc 1752.120.2 in macOS 26.5. Parsed by carta from the page's mdoc source.