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sysv_signal(3) [centos man page]

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/. 2007-05-04 SYSV_SIGNAL(3)

Check Out this Related Man Page

BSD_SIGNAL(3)						     Linux Programmer's Manual						     BSD_SIGNAL(3)

NAME
bsd_signal - signal handling with BSD semantics SYNOPSIS
#define _XOPEN_SOURCE /* See feature_test_macros(7) */ #include <signal.h> typedef void (*sighandler_t)(int); sighandler_t bsd_signal(int signum, sighandler_t handler); DESCRIPTION
The bsd_signal() function takes the same arguments, and performs the same task, as signal(2). The difference between the two is that bsd_signal() is guaranteed to provide reliable signal semantics, that is: a) the disposition of the signal is not reset to the default when the handler is invoked; b) delivery of further instances of the signal is blocked while the signal handler is executing; and c) if the handler interrupts a blocking system call, then the system call is automatically restarted. A portable application cannot rely on signal(2) to provide these guarantees. RETURN VALUE
The bsd_signal() function returns the previous value of the signal handler, or SIG_ERR on error. ERRORS
As for signal(2). CONFORMING TO
4.2BSD, POSIX.1-2001. POSIX.1-2008 removes the specification of bsd_signal(), recommending the use of sigaction(2) instead. NOTES
Use of bsd_signal() should be avoided; use sigaction(2) instead. On modern Linux systems, bsd_signal() and signal(2) are equivalent. But on older systems, signal(2) provided unreliable 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), sysv_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/. 2009-03-15 BSD_SIGNAL(3)

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