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Comparing cvsroot/Coro/Coro.pm (file contents):
Revision 1.273 by root, Fri Dec 11 18:32:23 2009 UTC vs.
Revision 1.283 by root, Sat Feb 5 21:20:47 2011 UTC

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81 81
82our $idle; # idle handler 82our $idle; # idle handler
83our $main; # main coro 83our $main; # main coro
84our $current; # current coro 84our $current; # current coro
85 85
86our $VERSION = 5.21; 86our $VERSION = 5.25;
87 87
88our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub rouse_cb rouse_wait); 88our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub rouse_cb rouse_wait);
89our %EXPORT_TAGS = ( 89our %EXPORT_TAGS = (
90 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)], 90 prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
91); 91);
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138 138
139See L<Coro::EV> or L<Coro::AnyEvent> for examples of using this technique. 139See L<Coro::EV> or L<Coro::AnyEvent> for examples of using this technique.
140 140
141=cut 141=cut
142 142
143# ||= because other modules could have provided their own by now
143$idle = new Coro sub { 144$idle ||= new Coro sub {
144 require Coro::Debug; 145 require Coro::Debug;
145 die "FATAL: deadlock detected.\n" 146 die "FATAL: deadlock detected.\n"
146 . Coro::Debug::ps_listing (); 147 . Coro::Debug::ps_listing ();
147}; 148};
148 149
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612Sets (or gets in case the argument is missing) the description for this 613Sets (or gets in case the argument is missing) the description for this
613coro. This is just a free-form string you can associate with a 614coro. This is just a free-form string you can associate with a
614coro. 615coro.
615 616
616This method simply sets the C<< $coro->{desc} >> member to the given 617This method simply sets the C<< $coro->{desc} >> member to the given
617string. You can modify this member directly if you wish. 618string. You can modify this member directly if you wish, and in fact, this
619is often preferred to indicate major processing states that cna then be
620seen for example in a L<Coro::Debug> session:
621
622 sub my_long_function {
623 local $Coro::current->{desc} = "now in my_long_function";
624 ...
625 $Coro::current->{desc} = "my_long_function: phase 1";
626 ...
627 $Coro::current->{desc} = "my_long_function: phase 2";
628 ...
629 }
618 630
619=cut 631=cut
620 632
621sub desc { 633sub desc {
622 my $old = $_[0]{desc}; 634 my $old = $_[0]{desc};
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659returning a new coderef. Unblocking means that calling the new coderef 671returning a new coderef. Unblocking means that calling the new coderef
660will return immediately without blocking, returning nothing, while the 672will return immediately without blocking, returning nothing, while the
661original code ref will be called (with parameters) from within another 673original code ref will be called (with parameters) from within another
662coro. 674coro.
663 675
664The reason this function exists is that many event libraries (such as the 676The reason this function exists is that many event libraries (such as
665venerable L<Event|Event> module) are not thread-safe (a weaker form 677the venerable L<Event|Event> module) are not thread-safe (a weaker form
666of reentrancy). This means you must not block within event callbacks, 678of reentrancy). This means you must not block within event callbacks,
667otherwise you might suffer from crashes or worse. The only event library 679otherwise you might suffer from crashes or worse. The only event library
668currently known that is safe to use without C<unblock_sub> is L<EV>. 680currently known that is safe to use without C<unblock_sub> is L<EV> (but
681you might still run into deadlocks if all event loops are blocked).
682
683Coro will try to catch you when you block in the event loop
684("FATAL:$Coro::IDLE blocked itself"), but this is just best effort and
685only works when you do not run your own event loop.
669 686
670This function allows your callbacks to block by executing them in another 687This function allows your callbacks to block by executing them in another
671coro where it is safe to block. One example where blocking is handy 688coro where it is safe to block. One example where blocking is handy
672is when you use the L<Coro::AIO|Coro::AIO> functions to save results to 689is when you use the L<Coro::AIO|Coro::AIO> functions to save results to
673disk, for example. 690disk, for example.
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740 757
741=back 758=back
742 759
743=cut 760=cut
744 761
762for my $module (qw(Channel RWLock Semaphore SemaphoreSet Signal Specific)) {
763 my $old = defined &{"Coro::$module\::new"} && \&{"Coro::$module\::new"};
764
765 *{"Coro::$module\::new"} = sub {
766 require "Coro/$module.pm";
767
768 # some modules have their new predefined in State.xs, some don't
769 *{"Coro::$module\::new"} = $old
770 if $old;
771
772 goto &{"Coro::$module\::new"};
773 };
774}
775
7451; 7761;
746 777
747=head1 HOW TO WAIT FOR A CALLBACK 778=head1 HOW TO WAIT FOR A CALLBACK
748 779
749It is very common for a coro to wait for some callback to be 780It is very common for a coro to wait for some callback to be
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852ithreads (for example, that memory or files would be shared), showing his 883ithreads (for example, that memory or files would be shared), showing his
853lack of understanding of this area - if it is hard to understand for Chip, 884lack of understanding of this area - if it is hard to understand for Chip,
854it is probably not obvious to everybody). 885it is probably not obvious to everybody).
855 886
856What follows is an ultra-condensed version of my talk about threads in 887What follows is an ultra-condensed version of my talk about threads in
857scripting languages given onthe perl workshop 2009: 888scripting languages given on the perl workshop 2009:
858 889
859The so-called "ithreads" were originally implemented for two reasons: 890The so-called "ithreads" were originally implemented for two reasons:
860first, to (badly) emulate unix processes on native win32 perls, and 891first, to (badly) emulate unix processes on native win32 perls, and
861secondly, to replace the older, real thread model ("5.005-threads"). 892secondly, to replace the older, real thread model ("5.005-threads").
862 893

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