gsignal (3)
Leading comments
Copyright (C) 2002 Andries Brouwer <aeb@cwi.nl> %%%LICENSE_START(VERBATIM) Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the L...
NAME
gsignal, ssignal - software signal facilitySYNOPSIS
#include <signal.h> typedef void (*sighandler_t)(int); int gsignal(int signum); sighandler_t ssignal(int signum, sighandler_t action);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
gsignal(), ssignal(): _SVID_SOURCE
DESCRIPTION
Don't use these functions under Linux. Due to a historical mistake, under Linux these functions are aliases for raise(3) and signal(2), respectively.Elsewhere, on System V-like systems, these functions implement software signaling, entirely independent of the classical signal(2) and kill(2) functions. The function ssignal() defines the action to take when the software signal with number signum is raised using the function gsignal(), and returns the previous such action or SIG_DFL. The function gsignal() does the following: if no action (or the action SIG_DFL) was specified for signum, then it does nothing and returns 0. If the action SIG_IGN was specified for signum, then it does nothing and returns 1. Otherwise, it resets the action to SIG_DFL and calls the action function with argument signum, and returns the value returned by that function. The range of possible values signum varies (often 1-15 or 1-17).
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).Interface | Attribute | Value |
gsignal() | Thread safety | MT-Safe |
ssignal() | Thread safety | MT-Safe sigintr |