NAME¶
Glib::Signal - Object customization and general purpose notification
DESCRIPTION¶
This page describes some functions related to signals in Glib. Since most things
you can do with signals are tied to Glib::Object instances, the majority of
the signal functions are documented there.
Thread safety¶
Some libraries, most notably GStreamer, sometimes invoke signal handlers from a
foreign thread that has no Perl interpreter associated with it. When this
happens, we have no choice but to hand the marshalling over to the main loop
which in turn later wakes up the main thread and lets it handle the request.
We cannot invoke the signal handler from the foreign thread since the Perl
interpreter may not be used concurrently.
The downside to this approach is that the foreign thread is blocked until the
main thread has finished executing the signal handler. This might lead to
deadlocks. It might help in this case to wrap the crucial parts of the signal
handler inside a Glib::Idle callback so that the signal handler can return
directly.
METHODS¶
integer = Glib-> install_exception_handler ($func, $data=undef)¶
- •
- $func (subroutine)
- •
- $data (scalar)
Install a subroutine to be executed when a signal emission traps an exception (a
croak or die).
$func should return boolean (true if the
handler should remain installed) and expect to receive a single scalar. This
scalar will be a private copy of $@ which the handler can mangle to its
heart's content.
Returns an identifier that may be used with
"remove_exception_handler".
See "gperl_install_exception_handler()" in Glib::xsapi.
Glib->remove_exception_handler ($tag)¶
- •
- $tag (integer)
Remove the exception handler identified by
$tag, as
returned by "install_exception_handler". If
$tag cannot be found, this does nothing.
WARNING: Do not call this function from within an exception handler. If you want
to remove your handler during its execution just have it return false.
See "gperl_remove_exception_handler()" in Glib::xsapi.
ENUMS AND FLAGS¶
flags Glib::SignalFlags¶
- •
- 'run-first' / 'G_SIGNAL_RUN_FIRST'
- •
- 'run-last' / 'G_SIGNAL_RUN_LAST'
- •
- 'run-cleanup' / 'G_SIGNAL_RUN_CLEANUP'
- •
- 'no-recurse' / 'G_SIGNAL_NO_RECURSE'
- •
- 'detailed' / 'G_SIGNAL_DETAILED'
- •
- 'action' / 'G_SIGNAL_ACTION'
- •
- 'no-hooks' / 'G_SIGNAL_NO_HOOKS'
SEE ALSO¶
Glib, Glib::Object
COPYRIGHT¶
Copyright (C) 2003-2011 by the gtk2-perl team.
This software is licensed under the LGPL. See Glib for a full notice.