SYSV_SIGNAL(3) |
Linux Programmer's Manual |
SYSV_SIGNAL(3) |
NAME
sysv_signal - signal handling with System V semantics
SYNOPSIS
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <signal.h>
typedef void (*sighandler_t)(int);
sighandler_t sysv_signal(int
signum
, sighandler_t
handler
);
DESCRIPTION
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.
RETURN VALUE
The
sysv_signal() function returns the previous value of the signal handler, or
SIG_ERR on error.
ERRORS
As for
signal(2).
CONFORMING TO
This function is nonstandard.
NOTES
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 defined only if the
_GNU_SOURCE feature test macro is defined.
SEE ALSO
sigaction(2),
signal(2),
bsd_signal(3),
signal(7)
COLOPHON
This page is part of release 3.53 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/.