raise_default_signal(3) - NetBSD Manual Pages

RAISE_DEFAULT_SIGNAL(3) NetBSD Library Functions ManualRAISE_DEFAULT_SIGNAL(3)


NAME

     raise_default_signal -- raise the default signal handler


LIBRARY

     System Utilities Library (libutil, -lutil)


SYNOPSIS

     #include <util.h>

     int
     raise_default_signal(int sig);


DESCRIPTION

     The raise_default_signal() function raises the default signal handler for
     the signal sig.  This function may be used by a user-defined signal han-
     dler router to ensure that a parent process receives the correct notifi-
     cation of a process termination by a signal.  This can be used to avoid a
     common programming mistake when terminating a process from a custom
     SIGINT or SIGQUIT signal handler.

     The operations performed are:

           1.   Block all signals, using sigprocmask(2).

           2.   Set the signal handler for signal sig to the default signal
                handler (SIG_DFL).

           3.   raise(3) signal sig.

           4.   Unblock signal sig to deliver it.

           5.   Restore the original signal mask and handler, even if there
                was a failure.

     See signal(7) for a table of signals and default actions.

     The raise_default_signal() function should be async-signal-safe.


RETURN VALUES

     Upon successful completion, a value of 0 is returned.  Otherwise, a value
     of -1 is returned and the global variable errno is set to indicate the
     error.


ERRORS

     The raise_default_signal() function may fail and set errno for any of the
     errors specified for the functions sigemptyset(3), sigfillset(3),
     sigaddset(3), sigprocmask(2), sigaction(2), or raise(3).


SEE ALSO

     sigaction(2), sigprocmask(2), raise(3), signal(7)


HISTORY

     The raise_default_signal() function first appeared in NetBSD 5.0.

NetBSD 9.3                    September 25, 2007                    NetBSD 9.3