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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.190 by root, Wed Nov 5 02:21:27 2008 UTC vs.
Revision 1.199 by root, Fri Mar 27 10:49:50 2009 UTC

137These watchers are normal Perl objects with normal Perl lifetime. After 137These watchers are normal Perl objects with normal Perl lifetime. After
138creating a watcher it will immediately "watch" for events and invoke the 138creating a watcher it will immediately "watch" for events and invoke the
139callback when the event occurs (of course, only when the event model 139callback when the event occurs (of course, only when the event model
140is in control). 140is in control).
141 141
142Note that B<callbacks must not permanently change global variables>
143potentially in use by the event loop (such as C<$_> or C<$[>) and that B<<
144callbacks must not C<die> >>. The former is good programming practise in
145Perl and the latter stems from the fact that exception handling differs
146widely between event loops.
147
142To disable the watcher you have to destroy it (e.g. by setting the 148To disable the watcher you have to destroy it (e.g. by setting the
143variable you store it in to C<undef> or otherwise deleting all references 149variable you store it in to C<undef> or otherwise deleting all references
144to it). 150to it).
145 151
146All watchers are created by calling a method on the C<AnyEvent> class. 152All watchers are created by calling a method on the C<AnyEvent> class.
162=head2 I/O WATCHERS 168=head2 I/O WATCHERS
163 169
164You can create an I/O watcher by calling the C<< AnyEvent->io >> method 170You can create an I/O watcher by calling the C<< AnyEvent->io >> method
165with the following mandatory key-value pairs as arguments: 171with the following mandatory key-value pairs as arguments:
166 172
167C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for events 173C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch
168(AnyEvent might or might not keep a reference to this file handle). C<poll> 174for events (AnyEvent might or might not keep a reference to this file
175handle). Note that only file handles pointing to things for which
176non-blocking operation makes sense are allowed. This includes sockets,
177most character devices, pipes, fifos and so on, but not for example files
178or block devices.
179
169must be a string that is either C<r> or C<w>, which creates a watcher 180C<poll> must be a string that is either C<r> or C<w>, which creates a
170waiting for "r"eadable or "w"ritable events, respectively. C<cb> is the 181watcher waiting for "r"eadable or "w"ritable events, respectively.
182
171callback to invoke each time the file handle becomes ready. 183C<cb> is the callback to invoke each time the file handle becomes ready.
172 184
173Although the callback might get passed parameters, their value and 185Although the callback might get passed parameters, their value and
174presence is undefined and you cannot rely on them. Portable AnyEvent 186presence is undefined and you cannot rely on them. Portable AnyEvent
175callbacks cannot use arguments passed to I/O watcher callbacks. 187callbacks cannot use arguments passed to I/O watcher callbacks.
176 188
861no warnings; 873no warnings;
862use strict qw(vars subs); 874use strict qw(vars subs);
863 875
864use Carp; 876use Carp;
865 877
866our $VERSION = 4.32; 878our $VERSION = 4.35;
867our $MODEL; 879our $MODEL;
868 880
869our $AUTOLOAD; 881our $AUTOLOAD;
870our @ISA; 882our @ISA;
871 883
1004# to support binding more than one watcher per filehandle (they usually 1016# to support binding more than one watcher per filehandle (they usually
1005# allow only one watcher per fd, so we dup it to get a different one). 1017# allow only one watcher per fd, so we dup it to get a different one).
1006sub _dupfh($$$$) { 1018sub _dupfh($$$$) {
1007 my ($poll, $fh, $r, $w) = @_; 1019 my ($poll, $fh, $r, $w) = @_;
1008 1020
1009 require Fcntl;
1010
1011 # cygwin requires the fh mode to be matching, unix doesn't 1021 # cygwin requires the fh mode to be matching, unix doesn't
1012 my ($rw, $mode) = $poll eq "r" ? ($r, "<") 1022 my ($rw, $mode) = $poll eq "r" ? ($r, "<")
1013 : $poll eq "w" ? ($w, ">") 1023 : $poll eq "w" ? ($w, ">")
1014 : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; 1024 : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
1015 1025
1043 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: 1053 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar::
1044} 1054}
1045 1055
1046# default implementation for ->signal 1056# default implementation for ->signal
1047 1057
1048our %SIG_CB; 1058our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1059
1060sub _signal_exec {
1061 sysread $SIGPIPE_R, my $dummy, 4;
1062
1063 while (%SIG_EV) {
1064 for (keys %SIG_EV) {
1065 delete $SIG_EV{$_};
1066 $_->() for values %{ $SIG_CB{$_} || {} };
1067 }
1068 }
1069}
1049 1070
1050sub signal { 1071sub signal {
1051 my (undef, %arg) = @_; 1072 my (undef, %arg) = @_;
1052 1073
1074 unless ($SIGPIPE_R) {
1075 if (AnyEvent::WIN32) {
1076 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1077 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1078 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1079 } else {
1080 pipe $SIGPIPE_R, $SIGPIPE_W;
1081 require Fcntl;
1082 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1083 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1084 }
1085
1086 $SIGPIPE_R
1087 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1088
1089 $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1090 }
1091
1053 my $signal = uc $arg{signal} 1092 my $signal = uc $arg{signal}
1054 or Carp::croak "required option 'signal' is missing"; 1093 or Carp::croak "required option 'signal' is missing";
1055 1094
1056 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1095 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1057 $SIG{$signal} ||= sub { 1096 $SIG{$signal} ||= sub {
1058 $_->() for values %{ $SIG_CB{$signal} || {} }; 1097 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1098 undef $SIG_EV{$signal};
1059 }; 1099 };
1060 1100
1061 bless [$signal, $arg{cb}], "AnyEvent::Base::Signal" 1101 bless [$signal, $arg{cb}], "AnyEvent::Base::Signal"
1062} 1102}
1063 1103
1263used, and preference will be given to protocols mentioned earlier in the 1303used, and preference will be given to protocols mentioned earlier in the
1264list. 1304list.
1265 1305
1266This variable can effectively be used for denial-of-service attacks 1306This variable can effectively be used for denial-of-service attacks
1267against local programs (e.g. when setuid), although the impact is likely 1307against local programs (e.g. when setuid), although the impact is likely
1268small, as the program has to handle connection errors already- 1308small, as the program has to handle conenction and other failures anyways.
1269 1309
1270Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, 1310Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,
1271but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> 1311but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1272- only support IPv4, never try to resolve or contact IPv6 1312- only support IPv4, never try to resolve or contact IPv6
1273addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or 1313addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1827=head1 BUGS 1867=head1 BUGS
1828 1868
1829Perl 5.8 has numerous memleaks that sometimes hit this module and are hard 1869Perl 5.8 has numerous memleaks that sometimes hit this module and are hard
1830to work around. If you suffer from memleaks, first upgrade to Perl 5.10 1870to work around. If you suffer from memleaks, first upgrade to Perl 5.10
1831and check wether the leaks still show up. (Perl 5.10.0 has other annoying 1871and check wether the leaks still show up. (Perl 5.10.0 has other annoying
1832mamleaks, such as leaking on C<map> and C<grep> but it is usually not as 1872memleaks, such as leaking on C<map> and C<grep> but it is usually not as
1833pronounced). 1873pronounced).
1834 1874
1835 1875
1836=head1 SEE ALSO 1876=head1 SEE ALSO
1837 1877

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