BSD_SIGNAL(3)		   Linux Programmers Manual		BSD_SIGNAL(3)



NAME
       bsd_signal - signal handling with BSD semantics

SYNOPSIS
       #define _XOPEN_SOURCE
       #include 

       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).

CONFORMING TO
       4.2BSD, POSIX.1-2001.

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 only defined
       if the _GNU_SOURCE feature test macro is defined.

SEE ALSO
       sigaction(2), signal(2), sysv_signal(3),  feature_test_macros(7),  sig
       nal(7)

COLOPHON
       This  page  is  part of release 3.05 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			 BSD_SIGNAL(3)