[ViewVC] Diff of: cvs/AnyEvent-Fork/Fork.pm

Comparing AnyEvent-Fork/Fork.pm (file contents):
Revision 1.54 by root, Fri Apr 26 17:24:05 2013 UTC vs.
Revision 1.72 by root, Tue Nov 5 02:44:27 2019 UTC

…		…
56	or L<AnyEvent::Subprocess>. There are modules that implement their own	56	or L<AnyEvent::Subprocess>. There are modules that implement their own
57	process management, such as L<AnyEvent::DBI>.	57	process management, such as L<AnyEvent::DBI>.
58		58
59	The problems that all these modules try to solve are real, however, none	59	The problems that all these modules try to solve are real, however, none
60	of them (from what I have seen) tackle the very real problems of unwanted	60	of them (from what I have seen) tackle the very real problems of unwanted
61	memory sharing, efficiency, not being able to use event processing or	61	memory sharing, efficiency or not being able to use event processing, GUI
62	similar modules in the processes they create.	62	toolkits or similar modules in the processes they create.
63		63
64	This module doesn't try to replace any of them - instead it tries to solve	64	This module doesn't try to replace any of them - instead it tries to solve
65	the problem of creating processes with a minimum of fuss and overhead (and	65	the problem of creating processes with a minimum of fuss and overhead (and
66	also luxury). Ideally, most of these would use AnyEvent::Fork internally,	66	also luxury). Ideally, most of these would use AnyEvent::Fork internally,
67	except they were written before AnyEvent:Fork was available, so obviously	67	except they were written before AnyEvent:Fork was available, so obviously
…		…
89		89
90	=item Forking usually creates a copy-on-write copy of the parent	90	=item Forking usually creates a copy-on-write copy of the parent
91	process.	91	process.
92		92
93	For example, modules or data files that are loaded will not use additional	93	For example, modules or data files that are loaded will not use additional
94	memory after a fork. When exec'ing a new process, modules and data files	94	memory after a fork. Exec'ing a new process, in contrast, means modules
95	might need to be loaded again, at extra CPU and memory cost. But when	95	and data files might need to be loaded again, at extra CPU and memory
96	forking, literally all data structures are copied - if the program frees	96	cost.
		97
		98	But when forking, you still create a copy of your data structures - if
97	them and replaces them by new data, the child processes will retain the	99	the program frees them and replaces them by new data, the child processes
98	old version even if it isn't used, which can suddenly and unexpectedly	100	will retain the old version even if it isn't used, which can suddenly and
99	increase memory usage when freeing memory.	101	unexpectedly increase memory usage when freeing memory.
100		102
		103	For example, L<Gtk2::CV> is an image viewer optimised for large
		104	directories (millions of pictures). It also forks subprocesses for
		105	thumbnail generation, which inherit the data structure that stores all
		106	file information. If the user changes the directory, it gets freed in
		107	the main process, leaving a copy in the thumbnailer processes. This can
		108	lead to many times the memory usage that would actually be required. The
		109	solution is to fork early (and being unable to dynamically generate more
		110	subprocesses or do this from a module)... or to use L<AnyEvent:Fork>.
		111
101	The trade-off is between more sharing with fork (which can be good or	112	There is a trade-off between more sharing with fork (which can be good or
102	bad), and no sharing with exec.	113	bad), and no sharing with exec.
103		114
104	This module allows the main program to do a controlled fork, and allows	115	This module allows the main program to do a controlled fork, and allows
105	modules to exec processes safely at any time. When creating a custom	116	modules to exec processes safely at any time. When creating a custom
106	process pool you can take advantage of data sharing via fork without	117	process pool you can take advantage of data sharing via fork without
…		…
111	shared and what isn't, at all times.	122	shared and what isn't, at all times.
112		123
113	=item Exec'ing a new perl process might be difficult.	124	=item Exec'ing a new perl process might be difficult.
114		125
115	For example, it is not easy to find the correct path to the perl	126	For example, it is not easy to find the correct path to the perl
116	interpreter - C<$^X> might not be a perl interpreter at all.	127	interpreter - C<$^X> might not be a perl interpreter at all. Worse, there
		128	might not even be a perl binary installed on the system.
117		129
118	This module tries hard to identify the correct path to the perl	130	This module tries hard to identify the correct path to the perl
119	interpreter. With a cooperative main program, exec'ing the interpreter	131	interpreter. With a cooperative main program, exec'ing the interpreter
120	might not even be necessary, but even without help from the main program,	132	might not even be necessary, but even without help from the main program,
121	it will still work when used from a module.	133	it will still work when used from a module.
…		…
127	and modules are no longer loadable because they refer to a different	139	and modules are no longer loadable because they refer to a different
128	perl version, or parts of a distribution are newer than the ones already	140	perl version, or parts of a distribution are newer than the ones already
129	loaded.	141	loaded.
130		142
131	This module supports creating pre-initialised perl processes to be used as	143	This module supports creating pre-initialised perl processes to be used as
132	a template for new processes.	144	a template for new processes at a later time, e.g. for use in a process
		145	pool.
133		146
134	=item Forking might be impossible when a program is running.	147	=item Forking might be impossible when a program is running.
135		148
136	For example, POSIX makes it almost impossible to fork from a	149	For example, POSIX makes it almost impossible to fork from a
137	multi-threaded program while doing anything useful in the child - in	150	multi-threaded program while doing anything useful in the child - in
138	fact, if your perl program uses POSIX threads (even indirectly via	151	fact, if your perl program uses POSIX threads (even indirectly via
139	e.g. L<IO::AIO> or L<threads>), you cannot call fork on the perl level	152	e.g. L<IO::AIO> or L<threads>), you cannot call fork on the perl level
140	anymore without risking corruption issues on a number of operating	153	anymore without risking memory corruption or worse on a number of
141	systems.	154	operating systems.
142		155
143	This module can safely fork helper processes at any time, by calling	156	This module can safely fork helper processes at any time, by calling
144	fork+exec in C, in a POSIX-compatible way (via L<Proc::FastSpawn>).	157	fork+exec in C, in a POSIX-compatible way (via L<Proc::FastSpawn>).
145		158
146	=item Parallel processing with fork might be inconvenient or difficult	159	=item Parallel processing with fork might be inconvenient or difficult
…		…
165		178
166	=back	179	=back
167		180
168	=head1 EXAMPLES	181	=head1 EXAMPLES
169		182
		183	This is where the wall of text ends and code speaks.
		184
170	=head2 Create a single new process, tell it to run your worker function.	185	=head2 Create a single new process, tell it to run your worker function.
171		186
172	AnyEvent::Fork	187	AnyEvent::Fork
173	->new	188	->new
174	->require ("MyModule")	189	->require ("MyModule")
…		…
185		200
186	sub worker {	201	sub worker {
187	my ($slave_filehandle) = @_;	202	my ($slave_filehandle) = @_;
188		203
189	# now $slave_filehandle is connected to the $master_filehandle	204	# now $slave_filehandle is connected to the $master_filehandle
190	# in the original prorcess. have fun!	205	# in the original process. have fun!
191	}	206	}
192		207
193	=head2 Create a pool of server processes all accepting on the same socket.	208	=head2 Create a pool of server processes all accepting on the same socket.
194		209
195	# create listener socket	210	# create listener socket
…		…
256		271
257	my $stderr = $cv->recv;	272	my $stderr = $cv->recv;
258		273
259	=head2 For stingy users: put the worker code into a C<DATA> section.	274	=head2 For stingy users: put the worker code into a C<DATA> section.
260		275
261	When you want to be stingy with files, you cna put your code into the	276	When you want to be stingy with files, you can put your code into the
262	C<DATA> section of your module (or program):	277	C<DATA> section of your module (or program):
263		278
264	use AnyEvent::Fork;	279	use AnyEvent::Fork;
265		280
266	AnyEvent::Fork	281	AnyEvent::Fork
…		…
276		291
277	=head2 For stingy standalone programs: do not rely on external files at	292	=head2 For stingy standalone programs: do not rely on external files at
278	all.	293	all.
279		294
280	For single-file scripts it can be inconvenient to rely on external	295	For single-file scripts it can be inconvenient to rely on external
281	files - even when using < C<DATA> section, you still need to C<exec>	296	files - even when using a C<DATA> section, you still need to C<exec> an
282	an external perl interpreter, which might not be available when using	297	external perl interpreter, which might not be available when using
283	L<App::Staticperl>, L<Urlader> or L<PAR::Packer> for example.	298	L<App::Staticperl>, L<Urlader> or L<PAR::Packer> for example.
284		299
285	Two modules help here - L<AnyEvent::Fork::Early> forks a template process	300	Two modules help here - L<AnyEvent::Fork::Early> forks a template process
286	for all further calls to C<new_exec>, and L<AnyEvent::Fork::Template>	301	for all further calls to C<new_exec>, and L<AnyEvent::Fork::Template>
287	forks the main program as a template process.	302	forks the main program as a template process.
…		…
304	my ($fh, @args) = @_;	319	my ($fh, @args) = @_;
305	...	320	...
306	}	321	}
307		322
308	# now preserve everything so far as AnyEvent::Fork object	323	# now preserve everything so far as AnyEvent::Fork object
309	# in §TEMPLATE.	324	# in $TEMPLATE.
310	use AnyEvent::Fork::Template;	325	use AnyEvent::Fork::Template;
311		326
312	# do not put code outside of BEGIN blocks until here	327	# do not put code outside of BEGIN blocks until here
313		328
314	# now use the $TEMPLATE process in any way you like	329	# now use the $TEMPLATE process in any way you like
…		…
450	use AnyEvent;	465	use AnyEvent;
451	use AnyEvent::Util ();	466	use AnyEvent::Util ();
452		467
453	use IO::FDPass;	468	use IO::FDPass;
454		469
455	our $VERSION = '1.0';	470	our $VERSION = 1.31;
456		471
457	# the early fork template process	472	# the early fork template process
458	our $EARLY;	473	our $EARLY;
459		474
460	# the empty template process	475	# the empty template process
…		…
485	my $self = shift;	500	my $self = shift;
486		501
487	# ideally, we would want to use "a (w/a)*" as format string, but perl	502	# ideally, we would want to use "a (w/a)*" as format string, but perl
488	# versions from at least 5.8.9 to 5.16.3 are all buggy and can't unpack	503	# versions from at least 5.8.9 to 5.16.3 are all buggy and can't unpack
489	# it.	504	# it.
490	push @{ $self->[QUEUE] }, pack "a N/a*", $_[0], $_[1];	505	push @{ $self->[QUEUE] }, pack "a L/a*", $_[0], $_[1];
491		506
492	$self->[WW] \|\|= AE::io $self->[FH], 1, sub {	507	$self->[WW] \|\|= AE::io $self->[FH], 1, sub {
493	do {	508	do {
494	# send the next "thing" in the queue - either a reference to an fh,	509	# send the next "thing" in the queue - either a reference to an fh,
495	# or a plain string.	510	# or a plain string.
…		…
541		556
542	if ($pid eq 0) {	557	if ($pid eq 0) {
543	require AnyEvent::Fork::Serve;	558	require AnyEvent::Fork::Serve;
544	$AnyEvent::Fork::Serve::OWNER = $parent;	559	$AnyEvent::Fork::Serve::OWNER = $parent;
545	close $fh;	560	close $fh;
546	$0 = "$_[1] of $parent";	561	$0 = "$parent AnyEvent::Fork/exec";
547	AnyEvent::Fork::Serve::serve ($slave);	562	AnyEvent::Fork::Serve::serve ($slave);
548	exit 0;	563	exit 0;
549	} elsif (!$pid) {	564	} elsif (!$pid) {
550	die "AnyEvent::Fork::Early/Template: unable to fork template process: $!";	565	die "AnyEvent::Fork::Early/Template: unable to fork template process: $!";
551	}	566	}
…		…
605		620
606	You should use C<new> whenever possible, except when having a template	621	You should use C<new> whenever possible, except when having a template
607	process around is unacceptable.	622	process around is unacceptable.
608		623
609	The path to the perl interpreter is divined using various methods - first	624	The path to the perl interpreter is divined using various methods - first
610	C<$^X> is investigated to see if the path ends with something that sounds	625	C<$^X> is investigated to see if the path ends with something that looks
611	as if it were the perl interpreter. Failing this, the module falls back to	626	as if it were the perl interpreter. Failing this, the module falls back to
612	using C<$Config::Config{perlpath}>.	627	using C<$Config::Config{perlpath}>.
613		628
		629	The path to perl can also be overridden by setting the global variable
		630	C<$AnyEvent::Fork::PERL> - it's value will be used for all subsequent
		631	invocations.
		632
614	=cut	633	=cut
		634
		635	our $PERL;
615		636
616	sub new_exec {	637	sub new_exec {
617	my ($self) = @_;	638	my ($self) = @_;
618		639
619	return $EARLY->fork	640	return $EARLY->fork
620	if $EARLY;	641	if $EARLY;
621		642
		643	unless (defined $PERL) {
622	# first find path of perl	644	# first find path of perl
623	my $perl = $;	645	my $perl = $^X;
624		646
625	# first we try $^X, but the path must be absolute (always on win32), and end in sth.	647	# first we try $^X, but the path must be absolute (always on win32), and end in sth.
626	# that looks like perl. this obviously only works for posix and win32	648	# that looks like perl. this obviously only works for posix and win32
627	unless (	649	unless (
628	($^O eq "MSWin32" \|\| $perl =~ m%^/%)	650	($^O eq "MSWin32" \|\| $perl =~ m%^/%)
629	&& $perl =~ m%[/\\]perl(?:[0-9]+(\.[0-9]+)+)?(\.exe)?$%i	651	&& $perl =~ m%[/\\]perl(?:[0-9]+(\.[0-9]+)+)?(\.exe)?$%i
630	) {	652	) {
631	# if it doesn't look perlish enough, try Config	653	# if it doesn't look perlish enough, try Config
632	require Config;	654	require Config;
633	$perl = $Config::Config{perlpath};	655	$perl = $Config::Config{perlpath};
634	$perl =~ s/(?:\Q$Config::Config{_exe}\E)?$/$Config::Config{_exe}/;	656	$perl =~ s/(?:\Q$Config::Config{_exe}\E)?$/$Config::Config{_exe}/;
		657	}
		658
		659	$PERL = $perl;
635	}	660	}
636		661
637	require Proc::FastSpawn;	662	require Proc::FastSpawn;
638		663
639	my ($fh, $slave) = AnyEvent::Util::portable_socketpair;	664	my ($fh, $slave) = AnyEvent::Util::portable_socketpair;
…		…
647	#local $ENV{PERL5LIB} = join ":", grep !ref, @INC;	672	#local $ENV{PERL5LIB} = join ":", grep !ref, @INC;
648	my %env = %ENV;	673	my %env = %ENV;
649	$env{PERL5LIB} = join +($^O eq "MSWin32" ? ";" : ":"), grep !ref, @INC;	674	$env{PERL5LIB} = join +($^O eq "MSWin32" ? ";" : ":"), grep !ref, @INC;
650		675
651	my $pid = Proc::FastSpawn::spawn (	676	my $pid = Proc::FastSpawn::spawn (
652	$perl,	677	$PERL,
653	["perl", "-MAnyEvent::Fork::Serve", "-e", "AnyEvent::Fork::Serve::me", fileno $slave, $$],	678	[$PERL, "-MAnyEvent::Fork::Serve", "-e", "AnyEvent::Fork::Serve::me", fileno $slave, $$],
654	[map "$_=$env{$_}", keys %env],	679	[map "$_=$env{$_}", keys %env],
655	) or die "unable to spawn AnyEvent::Fork server: $!";	680	) or die "unable to spawn AnyEvent::Fork server: $!";
656		681
657	$self->_new ($fh, $pid)	682	$self->_new ($fh, $pid)
658	}	683	}
659		684
660	=item $pid = $proc->pid	685	=item $pid = $proc->pid
661		686
662	Returns the process id of the process I<iff it is a direct child of the	687	Returns the process id of the process I<iff it is a direct child of the
663	process running AnyEvent::Fork>, and C<undef> otherwise.	688	process running AnyEvent::Fork>, and C<undef> otherwise. As a general
		689	rule (that you cannot rely upon), processes created via C<new_exec>,
		690	L<AnyEvent::Fork::Early> or L<AnyEvent::Fork::Template> are direct
		691	children, while all other processes are not.
664		692
665	Normally, only processes created via C<< AnyEvent::Fork->new_exec >> and	693	Or in other words, you do not normally have to take care of zombies for
666	L<AnyEvent::Fork::Template> are direct children, and you are responsible	694	processes created via C<new>, but when in doubt, or zombies are a problem,
667	to clean up their zombies when they die.	695	you need to check whether a process is a diretc child by calling this
668		696	method, and possibly creating a child watcher or reap it manually.
669	All other processes are not direct children, and will be cleaned up by
670	AnyEvent::Fork itself.
671		697
672	=cut	698	=cut
673		699
674	sub pid {	700	sub pid {
675	$_[0][PID]	701	$_[0][PID]
676	}	702	}
677		703
678	=item $proc = $proc->eval ($perlcode, @args)	704	=item $proc = $proc->eval ($perlcode, @args)
679		705
680	Evaluates the given C<$perlcode> as ... Perl code, while setting C<@_> to	706	Evaluates the given C<$perlcode> as ... Perl code, while setting C<@_>
681	the strings specified by C<@args>, in the "main" package.	707	to the strings specified by C<@args>, in the "main" package (so you can
		708	access the args using C<$_[0]> and so on, but not using implicit C<shit>
		709	as the latter works on C<@ARGV>).
682		710
683	This call is meant to do any custom initialisation that might be required	711	This call is meant to do any custom initialisation that might be required
684	(for example, the C<require> method uses it). It's not supposed to be used	712	(for example, the C<require> method uses it). It's not supposed to be used
685	to completely take over the process, use C<run> for that.	713	to completely take over the process, use C<run> for that.
686		714
…		…
694	C<send_xxx> methods, such as file handles. See the L<use AnyEvent::Fork as	722	C<send_xxx> methods, such as file handles. See the L<use AnyEvent::Fork as
695	a faster fork+exec> example to see it in action.	723	a faster fork+exec> example to see it in action.
696		724
697	Returns the process object for easy chaining of method calls.	725	Returns the process object for easy chaining of method calls.
698		726
		727	It's common to want to call an iniitalisation function with some
		728	arguments. Make sure you actually pass C<@_> to that function (for example
		729	by using C<&name> syntax), and do not just specify a function name:
		730
		731	$proc->eval ('&MyModule::init', $string1, $string2);
		732
699	=cut	733	=cut
700		734
701	sub eval {	735	sub eval {
702	my ($self, $code, @args) = @_;	736	my ($self, $code, @args) = @_;
703		737
…		…
806		840
807	Even if not used otherwise, the socket can be a good indicator for the	841	Even if not used otherwise, the socket can be a good indicator for the
808	existence of the process - if the other process exits, you get a readable	842	existence of the process - if the other process exits, you get a readable
809	event on it, because exiting the process closes the socket (if it didn't	843	event on it, because exiting the process closes the socket (if it didn't
810	create any children using fork).	844	create any children using fork).
		845
		846	=over 4
		847
		848	=item Compatibility to L<AnyEvent::Fork::Remote>
		849
		850	If you want to write code that works with both this module and
		851	L<AnyEvent::Fork::Remote>, you need to write your code so that it assumes
		852	there are two file handles for communications, which might not be unix
		853	domain sockets. The C<run> function should start like this:
		854
		855	sub run {
		856	my ($rfh, @args) = @_; # @args is your normal arguments
		857	my $wfh = fileno $rfh ? $rfh : *STDOUT;
		858
		859	# now use $rfh for reading and $wfh for writing
		860	}
		861
		862	This checks whether the passed file handle is, in fact, the process
		863	C<STDIN> handle. If it is, then the function was invoked visa
		864	L<AnyEvent::Fork::Remote>, so STDIN should be used for reading and
		865	C<STDOUT> should be used for writing.
		866
		867	In all other cases, the function was called via this module, and there is
		868	only one file handle that should be sued for reading and writing.
		869
		870	=back
811		871
812	Example: create a template for a process pool, pass a few strings, some	872	Example: create a template for a process pool, pass a few strings, some
813	file handles, then fork, pass one more string, and run some code.	873	file handles, then fork, pass one more string, and run some code.
814		874
815	my $pool = AnyEvent::Fork	875	my $pool = AnyEvent::Fork
…		…
849	$self->_cmd (r => $func);	909	$self->_cmd (r => $func);
850	}	910	}
851		911
852	=back	912	=back
853		913
854	=head2 ADVANCED METHODS	914
		915	=head2 CHILD PROCESS INTERFACE
		916
		917	This module has a limited API for use in child processes.
855		918
856	=over 4	919	=over 4
857		920
858	=item new_from_stdio AnyEvent::Fork $fh	921	=item @args = AnyEvent::Fork::Serve::run_args
859		922
860	Assume that you have a perl interpreter running (without any special	923	This function, which only exists before the C<run> method is called,
861	options or a program) somewhere and it has it's STDIN and STDOUT connected	924	returns the arguments that would be passed to the run function, and clears
862	to the C<$fh> somehow. I.e. exactly the state perl is in when you start it	925	them.
863	without any arguments:
864		926
865	perl	927	This is mainly useful to get any file handles passed via C<send_fh>, but
866		928	works for any arguments passed via C<< send_I<xxx> >> methods.
867	Then you can create an C<AnyEvent::Fork> object out of this perl
868	interpreter with this constructor.
869
870	When the usefulness of this isn't immediately clear, imagine you manage to
871	run a perl interpreter remotely (F<ssh remotemachine perl>), then you can
872	manage it mostly like a local C<AnyEvent::Fork> child.
873
874	This works without any module support, i.e. the remote F<perl> does not
875	need to have any special modules installed.
876
877	There are a number of limitations though: C<send_fh> will only work if the
878	L<IO::FDPass> module is loadable by the remote perl and the two processes
879	are connected in a way that let's L<IO::FDPass> do it's work.
880
881	This will therefore not work over a network connection. From this follows
882	that C<fork> will also not work under these circumstances, as it relies on
883	C<send_fh> internally.
884
885	Although not a limitation of this module, keep in mind that the
886	"communications socket" is simply C<STDIN>, and depending on how you
887	started F<perl> (e.g. via F<ssh>), it might only be half-duplex. This is
888	fine for C<AnyEvent::Fork>, but your C<run> function might want to use
889	C<STDIN> (or the "communications socket") for input and C<STDOUT> for
890	output.
891
892	You can support both cases by checking the C<fileno> of the handle passed
893	to your run function:
894
895	sub run {
896	my ($rfh) = @_;
897
898	my $wfh = fileno $rfh ? $rfh : *STDOUT;
899
900	# now use $rfh for reading and $wfh for writing
901	}
902
903	=cut
904
905	sub new_from_stdio {
906	my ($class, $fh) = @_;
907
908	my $self = $class->_new ($fh);
909
910	# send startup code
911	push @{ $self->[QUEUE] },
912	(do "AnyEvent/Fork/serve.pl")
913	. <<'EOF';
914
915	$OWNER = "another process";
916	$0 = "AnyEvent::Fork/stdio of $OWNER";
917
918	serve *STDIN;
919	__END__
920	EOF
921
922	# the data is only sent when the user requests additional things, which
923	# is likely early enough for our purposes.
924
925	$self
926	}
927		929
928	=back	930	=back
929		931
		932
930	=head2 EXPERIMENTAL METHODS	933	=head2 EXPERIMENTAL METHODS
931		934
932	These methods might go away completely or change behaviour, a any time.	935	These methods might go away completely or change behaviour, at any time.
933		936
934	=over 4	937	=over 4
935		938
936	=item $proc->to_fh ($cb->($fh)) # EXPERIMENTAL, MIGHT BE REMOVED	939	=item $proc->to_fh ($cb->($fh)) # EXPERIMENTAL, MIGHT BE REMOVED
937		940
…		…
939	the communications socket.	942	the communications socket.
940		943
941	The process object becomes unusable on return from this function - any	944	The process object becomes unusable on return from this function - any
942	further method calls result in undefined behaviour.	945	further method calls result in undefined behaviour.
943		946
944	The point of this method is to give you a file handle thta you cna pass	947	The point of this method is to give you a file handle that you can pass
945	to another process. In that other process, you can call C<new_from_fh	948	to another process. In that other process, you can call C<new_from_fh
946	AnyEvent::Fork> to create a new C<AnyEvent::Fork> object from it, thereby	949	AnyEvent::Fork $fh> to create a new C<AnyEvent::Fork> object from it,
947	effectively passing a fork object to another process.	950	thereby effectively passing a fork object to another process.
948		951
949	=cut	952	=cut
950		953
951	sub to_fh {	954	sub to_fh {
952	my ($self, $cb) = @_;	955	my ($self, $cb) = @_;
…		…
1119	Cygwin perl is not supported at the moment due to some hilarious	1122	Cygwin perl is not supported at the moment due to some hilarious
1120	shortcomings of its API - see L<IO::FDPoll> for more details. If you never	1123	shortcomings of its API - see L<IO::FDPoll> for more details. If you never
1121	use C<send_fh> and always use C<new_exec> to create processes, it should	1124	use C<send_fh> and always use C<new_exec> to create processes, it should
1122	work though.	1125	work though.
1123		1126
		1127	=head1 USING AnyEvent::Fork IN SUBPROCESSES
		1128
		1129	AnyEvent::Fork itself cannot generally be used in subprocesses. As long as
		1130	only one process ever forks new processes, sharing the template processes
		1131	is possible (you could use a pipe as a lock by writing a byte into it to
		1132	unlock, and reading the byte to lock for example)
		1133
		1134	To make concurrent calls possible after fork, you should get rid of the
		1135	template and early fork processes. AnyEvent::Fork will create a new
		1136	template process as needed.
		1137
		1138	undef $AnyEvent::Fork::EARLY;
		1139	undef $AnyEvent::Fork::TEMPLATE;
		1140
		1141	It doesn't matter whether you get rid of them in the parent or child after
		1142	a fork.
		1143
1124	=head1 SEE ALSO	1144	=head1 SEE ALSO
1125		1145
1126	L<AnyEvent::Fork::Early>, to avoid executing a perl interpreter at all	1146	L<AnyEvent::Fork::Early>, to avoid executing a perl interpreter at all
1127	(part of this distribution).	1147	(part of this distribution).
1128		1148
1129	L<AnyEvent::Fork::Template>, to create a process by forking the main	1149	L<AnyEvent::Fork::Template>, to create a process by forking the main
1130	program at a convenient time (part of this distribution).	1150	program at a convenient time (part of this distribution).
1131		1151
		1152	L<AnyEvent::Fork::Remote>, for another way to create processes that is
		1153	mostly compatible to this module and modules building on top of it, but
		1154	works better with remote processes.
		1155
1132	L<AnyEvent::Fork::RPC>, for simple RPC to child processes (on CPAN).	1156	L<AnyEvent::Fork::RPC>, for simple RPC to child processes (on CPAN).
1133		1157
1134	L<AnyEvent::Fork::Pool>, for simple worker process pool (on CPAN).	1158	L<AnyEvent::Fork::Pool>, for simple worker process pool (on CPAN).
1135		1159
1136	=head1 AUTHOR AND CONTACT INFORMATION	1160	=head1 AUTHOR AND CONTACT INFORMATION

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Comparing AnyEvent-Fork/Fork.pm (file contents): Revision 1.54 by root, Fri Apr 26 17:24:05 2013 UTC vs. Revision 1.72 by root, Tue Nov 5 02:44:27 2019 UTC

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Comparing AnyEvent-Fork/Fork.pm (file contents):
Revision 1.54 by root, Fri Apr 26 17:24:05 2013 UTC vs.
Revision 1.72 by root, Tue Nov 5 02:44:27 2019 UTC