=head1 NAME

POSIX::SigAction - represent a struct sigaction

=head1 SYNOPSIS

  $sigset    = POSIX::SigSet->new(SIGINT, SIGQUIT);
  $sigaction = POSIX::SigAction
     ->new(\&handler, $sigset, SA_NOCLDSTOP);

  $sigset    = $sigaction->mask;
  $sigaction->flags(SA_RESTART);
  $sigaction->safe(1);

=head1 DESCRIPTION

The C<POSIX::SigAction> object corresponds to the C C<struct sigaction>,
defined by C<signal.h>.

This module is a bit tricky: POSIX.pm contains the same code for
the C<POSIX::SigAction> namespace. However, we do not need POSIX.pm
but only the POSIX.xs component which has the namespace hard-coded.

=head1 METHODS

=head2 Constructors

=over 4

=item POSIX::SigAction-E<gt>B<new>(HANDLER, [SIGSET, [FLAGS]])

The first parameter is the handler, a code reference. The second parameter
is a L<POSIX::SigSet|POSIX::SigSet> object, it defaults to the empty set.  The third
parameter contains the C<sa_flags>, it defaults to 0.

This object will be destroyed automatically when it is no longer needed.  

=back

=head2 Accessors

=over 4

=item $obj-E<gt>B<flags>()

Accessor functions to get/set the values of a SigAction object.

=item $obj-E<gt>B<handler>()

=item $obj-E<gt>B<mask>()

=item $obj-E<gt>B<safe>()

Accessor function for the "safe signals" flag of a SigAction object; see
L<perlipc> for general information on safe (a.k.a. "deferred") signals.  If
you wish to handle a signal safely, use this accessor to set the "safe" flag
in the C<POSIX::SigAction> object:

   $sigaction->safe(1);

You may also examine the "safe" flag on the output action object which is
filled in when given as the third parameter to
L<POSIX::1003::Signals::sigaction()|POSIX::1003::Signals/"Standard POSIX">:

  sigaction(SIGINT, $new_action, $old_action);
  if ($old_action->safe) {
     # previous SIGINT handler used safe signals
  }

=back

=head1 SEE ALSO

This module is part of POSIX-1003 distribution version 0.13,
built on July 26, 2012. Website: F<http://perl.overmeer.net>.  The code is based on L<POSIX>, which
is released with Perl itself.  See also M<POSIX::Util> for
additional functionality.

=head1 COPYRIGHTS

Copyrights of the perl code and the related documentation by
2011-2012 by [Mark Overmeer]. For other contributors see ChangeLog.

This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
See F<http://www.perl.com/perl/misc/Artistic.html>