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Comparing AnyEvent-Fork/Fork.pm (file contents):
Revision 1.53 by root, Fri Apr 26 15:44:44 2013 UTC vs.
Revision 1.59 by root, Fri Aug 30 12:06:48 2013 UTC

… …
450use AnyEvent; 450use AnyEvent;
451use AnyEvent::Util (); 451use AnyEvent::Util ();
452 452
453use IO::FDPass; 453use IO::FDPass;
454 454
455our $VERSION = '1.0'; 455our $VERSION = 1.1;
456 456
457# the early fork template process 457# the early fork template process
458our $EARLY; 458our $EARLY;
459 459
460# the empty template process 460# the empty template process
… …
605 605
606You should use C<new> whenever possible, except when having a template 606You should use C<new> whenever possible, except when having a template
607process around is unacceptable. 607process around is unacceptable.
608 608
609The path to the perl interpreter is divined using various methods - first 609The path to the perl interpreter is divined using various methods - first
610C<$^X> is investigated to see if the path ends with something that sounds 610C<$^X> is investigated to see if the path ends with something that looks
611as if it were the perl interpreter. Failing this, the module falls back to 611as if it were the perl interpreter. Failing this, the module falls back to
612using C<$Config::Config{perlpath}>. 612using C<$Config::Config{perlpath}>.
613 613
614The path to perl can also be overriden by setting the global variable
615C<$AnyEvent::Fork::PERL> - it's value will be used for all subsequent
616invocations.
617
614=cut 618=cut
619
620our $PERL;
615 621
616sub new_exec { 622sub new_exec {
617 my ($self) = @_; 623 my ($self) = @_;
618 624
619 return $EARLY->fork 625 return $EARLY->fork
620 if $EARLY; 626 if $EARLY;
621 627
628 unless (defined $PERL) {
622 # first find path of perl 629 # first find path of perl
623 my $perl = $; 630 my $perl = $;
624 631
625 # first we try $^X, but the path must be absolute (always on win32), and end in sth. 632 # first we try $^X, but the path must be absolute (always on win32), and end in sth.
626 # that looks like perl. this obviously only works for posix and win32 633 # that looks like perl. this obviously only works for posix and win32
627 unless ( 634 unless (
628 ($^O eq "MSWin32" || $perl =~ m%^/%) 635 ($^O eq "MSWin32" || $perl =~ m%^/%)
629 && $perl =~ m%[/\\]perl(?:[0-9]+(\.[0-9]+)+)?(\.exe)?$%i 636 && $perl =~ m%[/\\]perl(?:[0-9]+(\.[0-9]+)+)?(\.exe)?$%i
630 ) { 637 ) {
631 # if it doesn't look perlish enough, try Config 638 # if it doesn't look perlish enough, try Config
632 require Config; 639 require Config;
633 $perl = $Config::Config{perlpath}; 640 $perl = $Config::Config{perlpath};
634 $perl =~ s/(?:\Q$Config::Config{_exe}\E)?$/$Config::Config{_exe}/; 641 $perl =~ s/(?:\Q$Config::Config{_exe}\E)?$/$Config::Config{_exe}/;
642 }
643
644 $PERL = $perl;
635 } 645 }
636 646
637 require Proc::FastSpawn; 647 require Proc::FastSpawn;
638 648
639 my ($fh, $slave) = AnyEvent::Util::portable_socketpair; 649 my ($fh, $slave) = AnyEvent::Util::portable_socketpair;
… …
647 #local $ENV{PERL5LIB} = join ":", grep !ref, @INC; 657 #local $ENV{PERL5LIB} = join ":", grep !ref, @INC;
648 my %env = %ENV; 658 my %env = %ENV;
649 $env{PERL5LIB} = join +($^O eq "MSWin32" ? ";" : ":"), grep !ref, @INC; 659 $env{PERL5LIB} = join +($^O eq "MSWin32" ? ";" : ":"), grep !ref, @INC;
650 660
651 my $pid = Proc::FastSpawn::spawn ( 661 my $pid = Proc::FastSpawn::spawn (
652 $perl, 662 $PERL,
653 ["perl", "-MAnyEvent::Fork::Serve", "-e", "AnyEvent::Fork::Serve::me", fileno $slave, $$], 663 ["perl", "-MAnyEvent::Fork::Serve", "-e", "AnyEvent::Fork::Serve::me", fileno $slave, $$],
654 [map "$_=$env{$_}", keys %env], 664 [map "$_=$env{$_}", keys %env],
655 ) or die "unable to spawn AnyEvent::Fork server: $!"; 665 ) or die "unable to spawn AnyEvent::Fork server: $!";
656 666
657 $self->_new ($fh, $pid) 667 $self->_new ($fh, $pid)
658} 668}
659 669
660=item $pid = $proc->pid 670=item $pid = $proc->pid
661 671
662Returns the process id of the process I<iff it is a direct child of the 672Returns the process id of the process I<iff it is a direct child of the
663process running AnyEvent::Fork>, and C<undef> otherwise. 673process running AnyEvent::Fork>, and C<undef> otherwise. As a general
674rule (that you cannot rely upon), processes created via C<new_exec>,
675L<AnyEvent::Fork::Early> or L<AnyEvent::Fork::Template> are direct
676children, while all other processes are not.
664 677
665Normally, only processes created via C<< AnyEvent::Fork->new_exec >> and 678Or in other words, you do not normally have to take care of zombies for
666L<AnyEvent::Fork::Template> are direct children, and you are responsible 679processes created via C<new>, but when in doubt, or zombies are a problem,
667to clean up their zombies when they die. 680you need to check whether a process is a diretc child by calling this
668 681method, and possibly creating a child watcher or reap it manually.
669All other processes are not direct children, and will be cleaned up by
670AnyEvent::Fork itself.
671 682
672=cut 683=cut
673 684
674sub pid { 685sub pid {
675 $_[0][PID] 686 $_[0][PID]
… …
806 817
807Even if not used otherwise, the socket can be a good indicator for the 818Even if not used otherwise, the socket can be a good indicator for the
808existence of the process - if the other process exits, you get a readable 819existence of the process - if the other process exits, you get a readable
809event on it, because exiting the process closes the socket (if it didn't 820event on it, because exiting the process closes the socket (if it didn't
810create any children using fork). 821create any children using fork).
822
823=over 4
824
825=item Compatibility to L<AnyEvent::Fork::Remote>
826
827If you want to write code that works with both this module and
828L<AnyEvent::Fork::Remote>, you need to write your code so that it assumes
829there are two file handles for communications, which might not be unix
830domain sockets. The C<run> function should start like this:
831
832 sub run {
833 my ($rfh, @args) = @_; # @args is your normal arguments
834 my $wfh = fileno $rfh ? $rfh : *STDOUT;
835
836 # now use $rfh for reading and $wfh for writing
837 }
838
839This checks whether the passed file handle is, in fact, the process
840C<STDIN> handle. If it is, then the function was invoked visa
841L<AnyEvent::Fork::Remote>, so STDIN should be used for reading and
842C<STDOUT> should be used for writing.
843
844In all other cases, the function was called via this module, and there is
845only one file handle that should be sued for reading and writing.
846
847=back
811 848
812Example: create a template for a process pool, pass a few strings, some 849Example: create a template for a process pool, pass a few strings, some
813file handles, then fork, pass one more string, and run some code. 850file handles, then fork, pass one more string, and run some code.
814 851
815 my $pool = AnyEvent::Fork 852 my $pool = AnyEvent::Fork
… …
849 $self->_cmd (r => $func); 886 $self->_cmd (r => $func);
850} 887}
851 888
852=back 889=back
853 890
854=head2 ADVANCED METHODS
855
856=over 4
857
858=item new_from_stdio AnyEvent::Fork $fh
859
860Assume that you have a perl interpreter running (without any special
861options or a program) somewhere and it has it's STDIN and STDOUT connected
862to the C<$fh> somehow. I.e. exactly the state perl is in when you start it
863without any arguments:
864
865 perl
866
867Then you can create an C<AnyEvent::Fork> object out of this perl
868interpreter with this constructor.
869
870When the usefulness of this isn't immediately clear, imagine you manage to
871run a perl interpreter remotely (F<ssh remotemachine perl>), then you can
872manage it mostly like a local C<AnyEvent::Fork> child.
873
874This works without any module support, i.e. the remote F<perl> does not
875need to have any special modules installed.
876
877There are a number of limitations though: C<send_fh> will only work if the
878L<IO::FDPass> module is loadable by the remote perl and the two processes
879are connected in a way that let's L<IO::FDPass> do it's work.
880
881This will therefore not work over a network conenction. From this follows
882that C<fork> will also not work under these circumstances, as it relies on
883C<send_fh> internally.
884
885=cut
886
887sub new_from_stdio {
888 my ($class, $fh) = @_;
889
890 my $self = $class->_new ($fh);
891
892 # send startup code
893 push @{ $self->[QUEUE] },
894 (do "AnyEvent/Fork/serve.pl")
895 . <<'EOF';
896{
897 open my $fh, "+<&0"
898 or die "AnyEvent::Fork::Serve::stdio: unable to open communications socket: $!\n";
899 open STDIN , ">&2";
900 open STDOUT, ">&2";
901
902 $OWNER = "another process";
903 $0 = "AnyEvent::Fork/stdio of $OWNER";
904
905 @_ = $fh;
906}
907
908&serve;
909__END__
910EOF
911
912 # the data is only sent when the user requests additional things, which
913 # is likely early enough for our purposes.
914
915 $self
916}
917
918=back
919
920=head2 EXPERIMENTAL METHODS 891=head2 EXPERIMENTAL METHODS
921 892
922These methods might go away completely or change behaviour, a any time. 893These methods might go away completely or change behaviour, at any time.
923 894
924=over 4 895=over 4
925 896
926=item $proc->to_fh ($cb->($fh)) # EXPERIMENTAL, MIGHT BE REMOVED 897=item $proc->to_fh ($cb->($fh)) # EXPERIMENTAL, MIGHT BE REMOVED
927 898
… …
929the communications socket. 900the communications socket.
930 901
931The process object becomes unusable on return from this function - any 902The process object becomes unusable on return from this function - any
932further method calls result in undefined behaviour. 903further method calls result in undefined behaviour.
933 904
934The point of this method is to give you a file handle thta you cna pass 905The point of this method is to give you a file handle that you can pass
935to another process. In that other process, you can call C<new_from_fh 906to another process. In that other process, you can call C<new_from_fh
936AnyEvent::Fork> to create a new C<AnyEvent::Fork> object from it, thereby 907AnyEvent::Fork $fh> to create a new C<AnyEvent::Fork> object from it,
937effectively passing a fork object to another process. 908thereby effectively passing a fork object to another process.
938 909
939=cut 910=cut
940 911
941sub to_fh { 912sub to_fh {
942 my ($self, $cb) = @_; 913 my ($self, $cb) = @_;
… …
1117(part of this distribution). 1088(part of this distribution).
1118 1089
1119L<AnyEvent::Fork::Template>, to create a process by forking the main 1090L<AnyEvent::Fork::Template>, to create a process by forking the main
1120program at a convenient time (part of this distribution). 1091program at a convenient time (part of this distribution).
1121 1092
1093L<AnyEvent::Fork::Remote>, for another way to create processes that is
1094mostly compatible to this module and modules building on top of it, but
1095works better with remote processes.
1096
1122L<AnyEvent::Fork::RPC>, for simple RPC to child processes (on CPAN). 1097L<AnyEvent::Fork::RPC>, for simple RPC to child processes (on CPAN).
1123 1098
1124L<AnyEvent::Fork::Pool>, for simple worker process pool (on CPAN). 1099L<AnyEvent::Fork::Pool>, for simple worker process pool (on CPAN).
1125 1100
1126=head1 AUTHOR AND CONTACT INFORMATION 1101=head1 AUTHOR AND CONTACT INFORMATION

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