Yolinux.com

bsd_signal manpage

Search topic Section


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  sys-
       tem  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 han-
       dler, or SIG_ERR on error.

ERRORS
       As for signal(2).

ATTRIBUTES
       For   an	  explanation	of   the  terms	 used  in  this	 section,  see
       attributes(7).

       +-------------+---------------+---------+
       |Interface    | Attribute     | Value   |
       +-------------+---------------+---------+
       |bsd_signal() | Thread safety | MT-Safe |
       +-------------+---------------+---------+
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 4.10 of the Linux  man-pages  project.   A
       description  of	the project, information about reporting bugs, and the
       latest	 version    of	  this	  page,	   can	   be	  found	    at
       https://www.kernel.org/doc/man-pages/.



				  2015-03-02			 BSD_SIGNAL(3)