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Comparing AnyEvent-Fork/Fork.pm (file contents):
Revision 1.49 by root, Fri Apr 19 12:56:53 2013 UTC vs.
Revision 1.55 by root, Fri Apr 26 23:24:30 2013 UTC

38 38
39If you need some form of RPC, you could use the L<AnyEvent::Fork::RPC> 39If you need some form of RPC, you could use the L<AnyEvent::Fork::RPC>
40companion module, which adds simple RPC/job queueing to a process created 40companion module, which adds simple RPC/job queueing to a process created
41by this module. 41by this module.
42 42
43And if you need some automatic process pool management on top of
44L<AnyEvent::Fork::RPC>, you can look at the L<AnyEvent::Fork::Pool>
45companion module.
46
43Or you can implement it yourself in whatever way you like, use some 47Or you can implement it yourself in whatever way you like: use some
44message-passing module such as L<AnyEvent::MP>, some pipe such as 48message-passing module such as L<AnyEvent::MP>, some pipe such as
45L<AnyEvent::ZeroMQ>, use L<AnyEvent::Handle> on both sides to send 49L<AnyEvent::ZeroMQ>, use L<AnyEvent::Handle> on both sides to send
46e.g. JSON or Storable messages, and so on. 50e.g. JSON or Storable messages, and so on.
47 51
48=head2 COMPARISON TO OTHER MODULES 52=head2 COMPARISON TO OTHER MODULES
250 ->send_arg ("/bin/echo", "hi") 254 ->send_arg ("/bin/echo", "hi")
251 ->run ("run", my $cv = AE::cv); 255 ->run ("run", my $cv = AE::cv);
252 256
253 my $stderr = $cv->recv; 257 my $stderr = $cv->recv;
254 258
259=head2 For stingy users: put the worker code into a C<DATA> section.
260
261When you want to be stingy with files, you cna put your code into the
262C<DATA> section of your module (or program):
263
264 use AnyEvent::Fork;
265
266 AnyEvent::Fork
267 ->new
268 ->eval (do { local $/; <DATA> })
269 ->run ("doit", sub { ... });
270
271 __DATA__
272
273 sub doit {
274 ... do something!
275 }
276
277=head2 For stingy standalone programs: do not rely on external files at
278all.
279
280For single-file scripts it can be inconvenient to rely on external
281files - even when using < C<DATA> section, you still need to C<exec>
282an external perl interpreter, which might not be available when using
283L<App::Staticperl>, L<Urlader> or L<PAR::Packer> for example.
284
285Two modules help here - L<AnyEvent::Fork::Early> forks a template process
286for all further calls to C<new_exec>, and L<AnyEvent::Fork::Template>
287forks the main program as a template process.
288
289Here is how your main program should look like:
290
291 #! perl
292
293 # optional, as the very first thing.
294 # in case modules want to create their own processes.
295 use AnyEvent::Fork::Early;
296
297 # next, load all modules you need in your template process
298 use Example::My::Module
299 use Example::Whatever;
300
301 # next, put your run function definition and anything else you
302 # need, but do not use code outside of BEGIN blocks.
303 sub worker_run {
304 my ($fh, @args) = @_;
305 ...
306 }
307
308 # now preserve everything so far as AnyEvent::Fork object
309 # in §TEMPLATE.
310 use AnyEvent::Fork::Template;
311
312 # do not put code outside of BEGIN blocks until here
313
314 # now use the $TEMPLATE process in any way you like
315
316 # for example: create 10 worker processes
317 my @worker;
318 my $cv = AE::cv;
319 for (1..10) {
320 $cv->begin;
321 $TEMPLATE->fork->send_arg ($_)->run ("worker_run", sub {
322 push @worker, shift;
323 $cv->end;
324 });
325 }
326 $cv->recv;
327
255=head1 CONCEPTS 328=head1 CONCEPTS
256 329
257This module can create new processes either by executing a new perl 330This module can create new processes either by executing a new perl
258process, or by forking from an existing "template" process. 331process, or by forking from an existing "template" process.
259 332
377use AnyEvent; 450use AnyEvent;
378use AnyEvent::Util (); 451use AnyEvent::Util ();
379 452
380use IO::FDPass; 453use IO::FDPass;
381 454
382our $VERSION = 0.7; 455our $VERSION = '1.0';
383 456
384# the early fork template process 457# the early fork template process
385our $EARLY; 458our $EARLY;
386 459
387# the empty template process 460# the empty template process
435 # send string 508 # send string
436 my $len = syswrite $self->[FH], $self->[QUEUE][0]; 509 my $len = syswrite $self->[FH], $self->[QUEUE][0];
437 510
438 unless ($len) { 511 unless ($len) {
439 return if $! == Errno::EAGAIN || $! == Errno::EWOULDBLOCK; 512 return if $! == Errno::EAGAIN || $! == Errno::EWOULDBLOCK;
440 undef $self->[3]; 513 undef $self->[WW];
441 die "AnyEvent::Fork: command write failure: $!"; 514 die "AnyEvent::Fork: command write failure: $!";
442 } 515 }
443 516
444 substr $self->[QUEUE][0], 0, $len, ""; 517 substr $self->[QUEUE][0], 0, $len, "";
445 shift @{ $self->[QUEUE] } unless length $self->[QUEUE][0]; 518 shift @{ $self->[QUEUE] } unless length $self->[QUEUE][0];
774 847
775 $self->[CB] = $cb; 848 $self->[CB] = $cb;
776 $self->_cmd (r => $func); 849 $self->_cmd (r => $func);
777} 850}
778 851
779=item $proc->to_fh ($cb->($fh)) 852=back
853
854=head2 EXPERIMENTAL METHODS
855
856These methods might go away completely or change behaviour, at any time.
857
858=over 4
859
860=item $proc->to_fh ($cb->($fh)) # EXPERIMENTAL, MIGHT BE REMOVED
780 861
781Flushes all commands out to the process and then calls the callback with 862Flushes all commands out to the process and then calls the callback with
782the communications socket. 863the communications socket.
783 864
784The process object becomes unusable on return from this function - any 865The process object becomes unusable on return from this function - any
785further method calls result in undefined behaviour. 866further method calls result in undefined behaviour.
786 867
787The point of this method is to give you a file handle thta you cna pass 868The point of this method is to give you a file handle thta you cna pass
788to another process. In that other process, you can call C<new_from_fh 869to another process. In that other process, you can call C<new_from_fh
789AnyEvent::Fork::RPC> to create a new C<AnyEvent::Fork> object from it, 870AnyEvent::Fork> to create a new C<AnyEvent::Fork> object from it, thereby
790thereby effectively passing a fork object to another process. 871effectively passing a fork object to another process.
791 872
792=cut 873=cut
793 874
794sub to_fh { 875sub to_fh {
795 my ($self, $cb) = @_; 876 my ($self, $cb) = @_;
800 $self->[CB]->($self->[FH]); 881 $self->[CB]->($self->[FH]);
801 @$self = (); 882 @$self = ();
802 } 883 }
803} 884}
804 885
805=item new_from_fh AnyEvent::Fork $fh 886=item new_from_fh AnyEvent::Fork $fh # EXPERIMENTAL, MIGHT BE REMOVED
806 887
807Takes a file handle originally rceeived by the C<to_fh> method and creates 888Takes a file handle originally rceeived by the C<to_fh> method and creates
808a new C<AnyEvent:Fork> object. The child process itself will not change in 889a new C<AnyEvent:Fork> object. The child process itself will not change in
809any way, i.e. it will keep all the modifications done to it before calling 890any way, i.e. it will keep all the modifications done to it before calling
810C<to_fh>. 891C<to_fh>.
972L<AnyEvent::Fork::Template>, to create a process by forking the main 1053L<AnyEvent::Fork::Template>, to create a process by forking the main
973program at a convenient time (part of this distribution). 1054program at a convenient time (part of this distribution).
974 1055
975L<AnyEvent::Fork::RPC>, for simple RPC to child processes (on CPAN). 1056L<AnyEvent::Fork::RPC>, for simple RPC to child processes (on CPAN).
976 1057
1058L<AnyEvent::Fork::Pool>, for simple worker process pool (on CPAN).
1059
977=head1 AUTHOR AND CONTACT INFORMATION 1060=head1 AUTHOR AND CONTACT INFORMATION
978 1061
979 Marc Lehmann <schmorp@schmorp.de> 1062 Marc Lehmann <schmorp@schmorp.de>
980 http://software.schmorp.de/pkg/AnyEvent-Fork 1063 http://software.schmorp.de/pkg/AnyEvent-Fork
981 1064

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