NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | CONFORMING TO | NOTES | SEE ALSO | COLOPHON
SYSV_SIGNAL(3) Linux Programmer's Manual SYSV_SIGNAL(3)
sysv_signal - signal handling with System V semantics
#define _GNU_SOURCE
#include <signal.h>
typedef void (*sighandler_t)(int);
sighandler_t sysv_signal(int signum, sighandler_t handler);
The sysv_signal() function takes the same arguments, and performs the same
task, as signal(2).
However sysv_signal() provides the System V unreliable signal semantics, that
is: a) the disposition of the signal is reset to the default when the handler
is invoked; b) delivery of further instances of the signal is not blocked
while the signal handler is executing; and c) if the handler interrupts
(certain) blocking system calls, then the system call is not automatically
restarted.
The sysv_signal() function returns the previous value of the signal handler,
or SIG_ERR on error.
As for signal(2).
This function is non-standard.
Use of sysv_signal() should be avoided; use sigaction(2) instead.
On older Linux systems, sysv_signal() and signal(2) were equivalent. But on
newer systems, signal(2) provides reliable signal semantics; see signal(2) for
details.
The use of sighandler_t is a GNU extension; this type is only defined if the
_GNU_SOURCE feature test macro is defined.
sigaction(2), signal(2), bsd_signal(3), feature_test_macros(7), signal(7)
This page is part of release 3.23 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
2007-05-04 SYSV_SIGNAL(3)