1Glib::Signal(3)       User Contributed Perl Documentation      Glib::Signal(3)
2
3
4

NAME

6       Glib::Signal -  Object customization and general purpose notification
7

DESCRIPTION

9       This page describes some functions related to signals in Glib.  Since
10       most things you can do with signals are tied to Glib::Object instances,
11       the majority of the signal functions are documented there.
12
13   Thread safety
14       Some libraries, most notably GStreamer, sometimes invoke signal
15       handlers from a foreign thread that has no Perl interpreter associated
16       with it.  When this happens, we have no choice but to hand the
17       marshalling over to the main loop which in turn later wakes up the main
18       thread and lets it handle the request.  We cannot invoke the signal
19       handler from the foreign thread since the Perl interpreter may not be
20       used concurrently.
21
22       The downside to this approach is that the foreign thread is blocked
23       until the main thread has finished executing the signal handler.  This
24       might lead to deadlocks.  It might help in this case to wrap the
25       crucial parts of the signal handler inside a Glib::Idle callback so
26       that the signal handler can return directly.
27

METHODS

29   integer = Glib->install_exception_handler ($func, $data=undef)
30       ·   $func (subroutine)
31
32       ·   $data (scalar)
33
34       Install a subroutine to be executed when a signal emission traps an
35       exception (a croak or die).  $func should return boolean (true if the
36       handler should remain installed) and expect to receive a single scalar.
37       This scalar will be a private copy of $@ which the handler can mangle
38       to its heart's content.
39
40       Returns an identifier that may be used with "remove_exception_handler".
41
42       See "gperl_install_exception_handler()" in Glib::xsapi.
43
44   Glib->remove_exception_handler ($tag)
45       ·   $tag (integer)
46
47       Remove the exception handler identified by $tag, as returned by
48       "install_exception_handler".  If $tag cannot be found, this does
49       nothing.
50
51       WARNING:  Do not call this function from within an exception handler.
52       If you want to remove your handler during its execution just have it
53       return false.
54
55       See "gperl_remove_exception_handler()" in Glib::xsapi.
56

ENUMS AND FLAGS

58   flags Glib::SignalFlags
59       ·   'run-first' / 'G_SIGNAL_RUN_FIRST'
60
61       ·   'run-last' / 'G_SIGNAL_RUN_LAST'
62
63       ·   'run-cleanup' / 'G_SIGNAL_RUN_CLEANUP'
64
65       ·   'no-recurse' / 'G_SIGNAL_NO_RECURSE'
66
67       ·   'detailed' / 'G_SIGNAL_DETAILED'
68
69       ·   'action' / 'G_SIGNAL_ACTION'
70
71       ·   'no-hooks' / 'G_SIGNAL_NO_HOOKS'
72

SEE ALSO

74       Glib, Glib::Object
75

77       Copyright (C) 2003-2011 by the gtk2-perl team.
78
79       This software is licensed under the LGPL.  See Glib for a full notice.
80
81
82
83perl v5.32.0                      2020-07-28                   Glib::Signal(3)
Impressum