bsd_signal(3)

1BSD_SIGNAL(3)              Linux Programmer's Manual             BSD_SIGNAL(3)
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NAME

6       bsd_signal - signal handling with BSD semantics
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SYNOPSIS

9       #define _XOPEN_SOURCE
10       #include <signal.h>
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12       typedef void (*sighandler_t)(int);
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14       sighandler_t bsd_signal(int signum, sighandler_t handler);
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DESCRIPTION

17       The  bsd_signal()  function  takes the same arguments, and performs the
18       same task, as signal(2).
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20       The difference between the two is that bsd_signal()  is  guaranteed  to
21       provide  reliable  signal semantics, that is: a) the disposition of the
22       signal is not reset to the default when  the  handler  is  invoked;  b)
23       delivery of further instances of the signal is blocked while the signal
24       handler is executing; and c) if the handler interrupts a blocking  sys‐
25       tem  call, then the system call is automatically restarted.  A portable
26       application cannot rely on signal(2) to provide these guarantees.
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RETURN VALUE

29       The bsd_signal() function returns the previous value of the signal han‐
30       dler, or SIG_ERR on error.
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ERRORS

33       As for signal(2).
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CONFORMING TO

36       4.2BSD,   POSIX.1-2001.   POSIX.1-2008  removes  the  specification  of
37       bsd_signal(), recommending the use of sigaction(2) instead.
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NOTES

40       Use of bsd_signal() should be avoided; use sigaction(2) instead.
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42       On modern Linux systems, bsd_signal()  and  signal(2)  are  equivalent.
43       But  on  older systems, signal(2) provided unreliable signal semantics;
44       see signal(2) for details.
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46       The use of sighandler_t is a GNU extension; this type is  only  defined
47       if the _GNU_SOURCE feature test macro is defined.
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COLOPHON

54       This page is part of release 3.25 of the Linux  man-pages  project.   A
55       description  of  the project, and information about reporting bugs, can
56       be found at http://www.kernel.org/doc/man-pages/.
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60                                  2009-03-15                     BSD_SIGNAL(3)