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1.1 |
=head1 NAME |
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1.4 |
AnyEvent::Fork - everything you wanted to use fork() for, but couldn't |
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1.1 |
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1.9 |
ATTENTION, this is a very early release, and very untested. Consider it a |
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technology preview. |
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1.1 |
=head1 SYNOPSIS |
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1.4 |
use AnyEvent::Fork; |
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1.1 |
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1.9 |
################################################################## |
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# create a single new process, tell it to run your worker function |
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AnyEvent::Fork |
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->new |
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->require ("MyModule") |
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->run ("MyModule::worker, sub { |
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my ($master_filehandle) = @_; |
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# now $master_filehandle is connected to the |
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# $slave_filehandle in the new process. |
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}); |
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# MyModule::worker might look like this |
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sub MyModule::worker { |
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my ($slave_filehandle) = @_; |
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# now $slave_filehandle is connected to the $master_filehandle |
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# in the original prorcess. have fun! |
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} |
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################################################################## |
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# create a pool of server processes all accepting on the same socket |
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# create listener socket |
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my $listener = ...; |
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# create a pool template, initialise it and give it the socket |
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my $pool = AnyEvent::Fork |
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->new |
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->require ("Some::Stuff", "My::Server") |
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->send_fh ($listener); |
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# now create 10 identical workers |
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for my $id (1..10) { |
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$pool |
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->fork |
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->send_arg ($id) |
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->run ("My::Server::run"); |
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} |
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# now do other things - maybe use the filehandle provided by run |
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# to wait for the processes to die. or whatever. |
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# My::Server::run might look like this |
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sub My::Server::run { |
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my ($slave, $listener, $id) = @_; |
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close $slave; # we do not use the socket, so close it to save resources |
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# we could go ballistic and use e.g. AnyEvent here, or IO::AIO, |
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# or anything we usually couldn't do in a process forked normally. |
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while (my $socket = $listener->accept) { |
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# do sth. with new socket |
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} |
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} |
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1.1 |
=head1 DESCRIPTION |
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1.4 |
This module allows you to create new processes, without actually forking |
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them from your current process (avoiding the problems of forking), but |
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preserving most of the advantages of fork. |
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It can be used to create new worker processes or new independent |
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subprocesses for short- and long-running jobs, process pools (e.g. for use |
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in pre-forked servers) but also to spawn new external processes (such as |
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CGI scripts from a webserver), which can be faster (and more well behaved) |
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than using fork+exec in big processes. |
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1.1 |
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1.5 |
Special care has been taken to make this module useful from other modules, |
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while still supporting specialised environments such as L<App::Staticperl> |
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or L<PAR::Packer>. |
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1.1 |
=head1 PROBLEM STATEMENT |
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There are two ways to implement parallel processing on UNIX like operating |
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systems - fork and process, and fork+exec and process. They have different |
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advantages and disadvantages that I describe below, together with how this |
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module tries to mitigate the disadvantages. |
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=over 4 |
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=item Forking from a big process can be very slow (a 5GB process needs |
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0.05s to fork on my 3.6GHz amd64 GNU/Linux box for example). This overhead |
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is often shared with exec (because you have to fork first), but in some |
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circumstances (e.g. when vfork is used), fork+exec can be much faster. |
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This module can help here by telling a small(er) helper process to fork, |
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or fork+exec instead. |
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=item Forking usually creates a copy-on-write copy of the parent |
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process. Memory (for example, modules or data files that have been |
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will not take additional memory). When exec'ing a new process, modules |
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and data files might need to be loaded again, at extra cpu and memory |
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cost. Likewise when forking, all data structures are copied as well - if |
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the program frees them and replaces them by new data, the child processes |
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will retain the memory even if it isn't used. |
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This module allows the main program to do a controlled fork, and allows |
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modules to exec processes safely at any time. When creating a custom |
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process pool you can take advantage of data sharing via fork without |
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risking to share large dynamic data structures that will blow up child |
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memory usage. |
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=item Exec'ing a new perl process might be difficult and slow. For |
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example, it is not easy to find the correct path to the perl interpreter, |
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and all modules have to be loaded from disk again. Long running processes |
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might run into problems when perl is upgraded for example. |
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This module supports creating pre-initialised perl processes to be used |
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as template, and also tries hard to identify the correct path to the perl |
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interpreter. With a cooperative main program, exec'ing the interpreter |
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might not even be necessary. |
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=item Forking might be impossible when a program is running. For example, |
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POSIX makes it almost impossible to fork from a multithreaded program and |
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do anything useful in the child - strictly speaking, if your perl program |
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uses posix threads (even indirectly via e.g. L<IO::AIO> or L<threads>), |
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you cannot call fork on the perl level anymore, at all. |
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This module can safely fork helper processes at any time, by caling |
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fork+exec in C, in a POSIX-compatible way. |
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=item Parallel processing with fork might be inconvenient or difficult |
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to implement. For example, when a program uses an event loop and creates |
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watchers it becomes very hard to use the event loop from a child |
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program, as the watchers already exist but are only meaningful in the |
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parent. Worse, a module might want to use such a system, not knowing |
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whether another module or the main program also does, leading to problems. |
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This module only lets the main program create pools by forking (because |
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only the main program can know when it is still safe to do so) - all other |
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pools are created by fork+exec, after which such modules can again be |
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loaded. |
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=back |
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root |
1.3 |
=head1 CONCEPTS |
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This module can create new processes either by executing a new perl |
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process, or by forking from an existing "template" process. |
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Each such process comes with its own file handle that can be used to |
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communicate with it (it's actually a socket - one end in the new process, |
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one end in the main process), and among the things you can do in it are |
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load modules, fork new processes, send file handles to it, and execute |
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functions. |
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There are multiple ways to create additional processes to execute some |
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jobs: |
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=over 4 |
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=item fork a new process from the "default" template process, load code, |
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run it |
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This module has a "default" template process which it executes when it is |
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needed the first time. Forking from this process shares the memory used |
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for the perl interpreter with the new process, but loading modules takes |
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time, and the memory is not shared with anything else. |
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This is ideal for when you only need one extra process of a kind, with the |
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option of starting and stipping it on demand. |
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root |
1.9 |
Example: |
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AnyEvent::Fork |
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->new |
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->require ("Some::Module") |
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->run ("Some::Module::run", sub { |
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my ($fork_fh) = @_; |
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}); |
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1.3 |
=item fork a new template process, load code, then fork processes off of |
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it and run the code |
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When you need to have a bunch of processes that all execute the same (or |
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very similar) tasks, then a good way is to create a new template process |
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for them, loading all the modules you need, and then create your worker |
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processes from this new template process. |
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This way, all code (and data structures) that can be shared (e.g. the |
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modules you loaded) is shared between the processes, and each new process |
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consumes relatively little memory of its own. |
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The disadvantage of this approach is that you need to create a template |
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process for the sole purpose of forking new processes from it, but if you |
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only need a fixed number of proceses you can create them, and then destroy |
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the template process. |
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1.9 |
Example: |
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my $template = AnyEvent::Fork->new->require ("Some::Module"); |
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for (1..10) { |
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$template->fork->run ("Some::Module::run", sub { |
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my ($fork_fh) = @_; |
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}); |
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} |
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# at this point, you can keep $template around to fork new processes |
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# later, or you can destroy it, which causes it to vanish. |
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1.3 |
=item execute a new perl interpreter, load some code, run it |
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This is relatively slow, and doesn't allow you to share memory between |
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multiple processes. |
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The only advantage is that you don't have to have a template process |
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hanging around all the time to fork off some new processes, which might be |
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an advantage when there are long time spans where no extra processes are |
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needed. |
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1.9 |
Example: |
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AnyEvent::Fork |
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->new_exec |
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->require ("Some::Module") |
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->run ("Some::Module::run", sub { |
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my ($fork_fh) = @_; |
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}); |
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1.3 |
=back |
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=head1 FUNCTIONS |
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root |
1.1 |
=over 4 |
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=cut |
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root |
1.4 |
package AnyEvent::Fork; |
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1.1 |
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use common::sense; |
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use Socket (); |
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use AnyEvent; |
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1.4 |
use AnyEvent::Fork::Util; |
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1.1 |
use AnyEvent::Util (); |
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1.4 |
our $PERL; # the path to the perl interpreter, deduces with various forms of magic |
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1.1 |
|
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1.4 |
=item my $pool = new AnyEvent::Fork key => value... |
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1.1 |
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Create a new process pool. The following named parameters are supported: |
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=over 4 |
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=back |
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=cut |
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root |
1.5 |
# the early fork template process |
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our $EARLY; |
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1.4 |
# the empty template process |
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our $TEMPLATE; |
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sub _cmd { |
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my $self = shift; |
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1.9 |
#TODO: maybe append the packet to any existing string command already in the queue |
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1.4 |
# ideally, we would want to use "a (w/a)*" as format string, but perl versions |
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1.5 |
# from at least 5.8.9 to 5.16.3 are all buggy and can't unpack it. |
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1.11 |
push @{ $self->[2] }, pack "N/a*", pack "(w/a*)*", @_; |
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1.4 |
|
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$self->[3] ||= AE::io $self->[1], 1, sub { |
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1.9 |
# send the next "thing" in the queue - either a reference to an fh, |
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# or a plain string. |
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1.4 |
if (ref $self->[2][0]) { |
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1.9 |
# send fh |
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1.4 |
AnyEvent::Fork::Util::fd_send fileno $self->[1], fileno ${ $self->[2][0] } |
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and shift @{ $self->[2] }; |
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1.5 |
|
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1.4 |
} else { |
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1.9 |
# send string |
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1.4 |
my $len = syswrite $self->[1], $self->[2][0] |
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or do { undef $self->[3]; die "AnyEvent::Fork: command write failure: $!" }; |
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1.5 |
|
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1.4 |
substr $self->[2][0], 0, $len, ""; |
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shift @{ $self->[2] } unless length $self->[2][0]; |
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} |
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unless (@{ $self->[2] }) { |
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undef $self->[3]; |
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1.9 |
# invoke run callback |
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1.4 |
$self->[0]->($self->[1]) if $self->[0]; |
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} |
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}; |
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} |
304 |
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1.1 |
|
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1.4 |
sub _new { |
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my ($self, $fh) = @_; |
307 |
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1.1 |
|
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1.6 |
AnyEvent::Util::fh_nonblocking $fh, 1; |
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1.4 |
$self = bless [ |
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undef, # run callback |
312 |
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1.1 |
$fh, |
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1.4 |
[], # write queue - strings or fd's |
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undef, # AE watcher |
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], $self; |
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$self |
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1.1 |
} |
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1.6 |
# fork template from current process, used by AnyEvent::Fork::Early/Template |
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sub _new_fork { |
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my ($fh, $slave) = AnyEvent::Util::portable_socketpair; |
323 |
root |
1.7 |
my $parent = $$; |
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1.6 |
my $pid = fork; |
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327 |
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if ($pid eq 0) { |
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require AnyEvent::Fork::Serve; |
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1.7 |
$AnyEvent::Fork::Serve::OWNER = $parent; |
330 |
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1.6 |
close $fh; |
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1.7 |
$0 = "$_[1] of $parent"; |
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1.6 |
AnyEvent::Fork::Serve::serve ($slave); |
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AnyEvent::Fork::Util::_exit 0; |
334 |
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} elsif (!$pid) { |
335 |
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die "AnyEvent::Fork::Early/Template: unable to fork template process: $!"; |
336 |
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} |
337 |
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AnyEvent::Fork->_new ($fh) |
339 |
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} |
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root |
1.4 |
=item my $proc = new AnyEvent::Fork |
342 |
root |
1.1 |
|
343 |
root |
1.4 |
Create a new "empty" perl interpreter process and returns its process |
344 |
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object for further manipulation. |
345 |
root |
1.1 |
|
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1.4 |
The new process is forked from a template process that is kept around |
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for this purpose. When it doesn't exist yet, it is created by a call to |
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C<new_exec> and kept around for future calls. |
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|
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root |
1.9 |
When the process object is destroyed, it will release the file handle |
351 |
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that connects it with the new process. When the new process has not yet |
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called C<run>, then the process will exit. Otherwise, what happens depends |
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entirely on the code that is executed. |
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root |
1.4 |
=cut |
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357 |
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sub new { |
358 |
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my $class = shift; |
359 |
root |
1.1 |
|
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1.4 |
$TEMPLATE ||= $class->new_exec; |
361 |
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$TEMPLATE->fork |
362 |
root |
1.1 |
} |
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1.4 |
=item $new_proc = $proc->fork |
365 |
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366 |
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Forks C<$proc>, creating a new process, and returns the process object |
367 |
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of the new process. |
368 |
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If any of the C<send_> functions have been called before fork, then they |
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will be cloned in the child. For example, in a pre-forked server, you |
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might C<send_fh> the listening socket into the template process, and then |
372 |
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keep calling C<fork> and C<run>. |
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=cut |
375 |
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376 |
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sub fork { |
377 |
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my ($self) = @_; |
378 |
root |
1.1 |
|
379 |
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my ($fh, $slave) = AnyEvent::Util::portable_socketpair; |
380 |
root |
1.4 |
|
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$self->send_fh ($slave); |
382 |
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$self->_cmd ("f"); |
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|
|
AnyEvent::Fork->_new ($fh) |
385 |
|
|
} |
386 |
|
|
|
387 |
|
|
=item my $proc = new_exec AnyEvent::Fork |
388 |
|
|
|
389 |
|
|
Create a new "empty" perl interpreter process and returns its process |
390 |
|
|
object for further manipulation. |
391 |
|
|
|
392 |
|
|
Unlike the C<new> method, this method I<always> spawns a new perl process |
393 |
|
|
(except in some cases, see L<AnyEvent::Fork::Early> for details). This |
394 |
|
|
reduces the amount of memory sharing that is possible, and is also slower. |
395 |
|
|
|
396 |
|
|
You should use C<new> whenever possible, except when having a template |
397 |
|
|
process around is unacceptable. |
398 |
|
|
|
399 |
|
|
The path to the perl interpreter is divined usign various methods - first |
400 |
|
|
C<$^X> is investigated to see if the path ends with something that sounds |
401 |
|
|
as if it were the perl interpreter. Failing this, the module falls back to |
402 |
|
|
using C<$Config::Config{perlpath}>. |
403 |
|
|
|
404 |
|
|
=cut |
405 |
|
|
|
406 |
|
|
sub new_exec { |
407 |
|
|
my ($self) = @_; |
408 |
|
|
|
409 |
root |
1.5 |
return $EARLY->fork |
410 |
|
|
if $EARLY; |
411 |
|
|
|
412 |
root |
1.4 |
# first find path of perl |
413 |
|
|
my $perl = $; |
414 |
|
|
|
415 |
|
|
# first we try $^X, but the path must be absolute (always on win32), and end in sth. |
416 |
|
|
# that looks like perl. this obviously only works for posix and win32 |
417 |
|
|
unless ( |
418 |
|
|
(AnyEvent::Fork::Util::WIN32 || $perl =~ m%^/%) |
419 |
|
|
&& $perl =~ m%[/\\]perl(?:[0-9]+(\.[0-9]+)+)?(\.exe)?$%i |
420 |
|
|
) { |
421 |
|
|
# if it doesn't look perlish enough, try Config |
422 |
|
|
require Config; |
423 |
|
|
$perl = $Config::Config{perlpath}; |
424 |
|
|
$perl =~ s/(?:\Q$Config::Config{_exe}\E)?$/$Config::Config{_exe}/; |
425 |
|
|
} |
426 |
|
|
|
427 |
|
|
require Proc::FastSpawn; |
428 |
|
|
|
429 |
|
|
my ($fh, $slave) = AnyEvent::Util::portable_socketpair; |
430 |
|
|
Proc::FastSpawn::fd_inherit (fileno $slave); |
431 |
|
|
|
432 |
root |
1.10 |
# new fh's should always be set cloexec (due to $^F), |
433 |
|
|
# but hey, not on win32, so we always clear the inherit flag. |
434 |
|
|
Proc::FastSpawn::fd_inherit (fileno $fh, 0); |
435 |
|
|
|
436 |
root |
1.4 |
# quick. also doesn't work in win32. of course. what did you expect |
437 |
|
|
#local $ENV{PERL5LIB} = join ":", grep !ref, @INC; |
438 |
root |
1.1 |
my %env = %ENV; |
439 |
root |
1.8 |
$env{PERL5LIB} = join +(AnyEvent::Fork::Util::WIN32 ? ";" : ":"), grep !ref, @INC; |
440 |
root |
1.1 |
|
441 |
root |
1.4 |
Proc::FastSpawn::spawn ( |
442 |
|
|
$perl, |
443 |
root |
1.7 |
["perl", "-MAnyEvent::Fork::Serve", "-e", "AnyEvent::Fork::Serve::me", fileno $slave, $$], |
444 |
root |
1.4 |
[map "$_=$env{$_}", keys %env], |
445 |
|
|
) or die "unable to spawn AnyEvent::Fork server: $!"; |
446 |
|
|
|
447 |
|
|
$self->_new ($fh) |
448 |
|
|
} |
449 |
|
|
|
450 |
root |
1.9 |
=item $proc = $proc->eval ($perlcode, @args) |
451 |
|
|
|
452 |
|
|
Evaluates the given C<$perlcode> as ... perl code, while setting C<@_> to |
453 |
|
|
the strings specified by C<@args>. |
454 |
|
|
|
455 |
|
|
This call is meant to do any custom initialisation that might be required |
456 |
|
|
(for example, the C<require> method uses it). It's not supposed to be used |
457 |
|
|
to completely take over the process, use C<run> for that. |
458 |
|
|
|
459 |
|
|
The code will usually be executed after this call returns, and there is no |
460 |
|
|
way to pass anything back to the calling process. Any evaluation errors |
461 |
|
|
will be reported to stderr and cause the process to exit. |
462 |
|
|
|
463 |
|
|
Returns the process object for easy chaining of method calls. |
464 |
|
|
|
465 |
|
|
=cut |
466 |
|
|
|
467 |
|
|
sub eval { |
468 |
|
|
my ($self, $code, @args) = @_; |
469 |
|
|
|
470 |
|
|
$self->_cmd (e => $code, @args); |
471 |
|
|
|
472 |
|
|
$self |
473 |
|
|
} |
474 |
|
|
|
475 |
root |
1.4 |
=item $proc = $proc->require ($module, ...) |
476 |
root |
1.1 |
|
477 |
root |
1.9 |
Tries to load the given module(s) into the process |
478 |
root |
1.1 |
|
479 |
root |
1.4 |
Returns the process object for easy chaining of method calls. |
480 |
root |
1.1 |
|
481 |
root |
1.9 |
=cut |
482 |
|
|
|
483 |
|
|
sub require { |
484 |
|
|
my ($self, @modules) = @_; |
485 |
|
|
|
486 |
|
|
s%::%/%g for @modules; |
487 |
|
|
$self->eval ('require "$_.pm" for @_', @modules); |
488 |
|
|
|
489 |
|
|
$self |
490 |
|
|
} |
491 |
|
|
|
492 |
root |
1.4 |
=item $proc = $proc->send_fh ($handle, ...) |
493 |
root |
1.1 |
|
494 |
root |
1.4 |
Send one or more file handles (I<not> file descriptors) to the process, |
495 |
|
|
to prepare a call to C<run>. |
496 |
root |
1.1 |
|
497 |
root |
1.4 |
The process object keeps a reference to the handles until this is done, |
498 |
|
|
so you must not explicitly close the handles. This is most easily |
499 |
|
|
accomplished by simply not storing the file handles anywhere after passing |
500 |
|
|
them to this method. |
501 |
|
|
|
502 |
|
|
Returns the process object for easy chaining of method calls. |
503 |
|
|
|
504 |
root |
1.9 |
Example: pass an fh to a process, and release it without closing. it will |
505 |
|
|
be closed automatically when it is no longer used. |
506 |
|
|
|
507 |
|
|
$proc->send_fh ($my_fh); |
508 |
|
|
undef $my_fh; # free the reference if you want, but DO NOT CLOSE IT |
509 |
|
|
|
510 |
root |
1.4 |
=cut |
511 |
|
|
|
512 |
|
|
sub send_fh { |
513 |
|
|
my ($self, @fh) = @_; |
514 |
|
|
|
515 |
|
|
for my $fh (@fh) { |
516 |
|
|
$self->_cmd ("h"); |
517 |
|
|
push @{ $self->[2] }, \$fh; |
518 |
|
|
} |
519 |
|
|
|
520 |
|
|
$self |
521 |
root |
1.1 |
} |
522 |
|
|
|
523 |
root |
1.4 |
=item $proc = $proc->send_arg ($string, ...) |
524 |
|
|
|
525 |
|
|
Send one or more argument strings to the process, to prepare a call to |
526 |
|
|
C<run>. The strings can be any octet string. |
527 |
|
|
|
528 |
|
|
Returns the process object for easy chaining of emthod calls. |
529 |
|
|
|
530 |
|
|
=cut |
531 |
root |
1.1 |
|
532 |
root |
1.4 |
sub send_arg { |
533 |
|
|
my ($self, @arg) = @_; |
534 |
root |
1.1 |
|
535 |
root |
1.4 |
$self->_cmd (a => @arg); |
536 |
root |
1.1 |
|
537 |
|
|
$self |
538 |
|
|
} |
539 |
|
|
|
540 |
root |
1.4 |
=item $proc->run ($func, $cb->($fh)) |
541 |
|
|
|
542 |
|
|
Enter the function specified by the fully qualified name in C<$func> in |
543 |
|
|
the process. The function is called with the communication socket as first |
544 |
|
|
argument, followed by all file handles and string arguments sent earlier |
545 |
|
|
via C<send_fh> and C<send_arg> methods, in the order they were called. |
546 |
|
|
|
547 |
|
|
If the called function returns, the process exits. |
548 |
|
|
|
549 |
|
|
Preparing the process can take time - when the process is ready, the |
550 |
|
|
callback is invoked with the local communications socket as argument. |
551 |
|
|
|
552 |
|
|
The process object becomes unusable on return from this function. |
553 |
|
|
|
554 |
|
|
If the communication socket isn't used, it should be closed on both sides, |
555 |
|
|
to save on kernel memory. |
556 |
|
|
|
557 |
|
|
The socket is non-blocking in the parent, and blocking in the newly |
558 |
|
|
created process. The close-on-exec flag is set on both. Even if not used |
559 |
|
|
otherwise, the socket can be a good indicator for the existance of the |
560 |
root |
1.8 |
process - if the other process exits, you get a readable event on it, |
561 |
root |
1.4 |
because exiting the process closes the socket (if it didn't create any |
562 |
|
|
children using fork). |
563 |
|
|
|
564 |
root |
1.9 |
Example: create a template for a process pool, pass a few strings, some |
565 |
|
|
file handles, then fork, pass one more string, and run some code. |
566 |
|
|
|
567 |
|
|
my $pool = AnyEvent::Fork |
568 |
|
|
->new |
569 |
|
|
->send_arg ("str1", "str2") |
570 |
|
|
->send_fh ($fh1, $fh2); |
571 |
|
|
|
572 |
|
|
for (1..2) { |
573 |
|
|
$pool |
574 |
|
|
->fork |
575 |
|
|
->send_arg ("str3") |
576 |
|
|
->run ("Some::function", sub { |
577 |
|
|
my ($fh) = @_; |
578 |
|
|
|
579 |
|
|
# fh is nonblocking, but we trust that the OS can accept these |
580 |
|
|
# extra 3 octets anyway. |
581 |
|
|
syswrite $fh, "hi #$_\n"; |
582 |
|
|
|
583 |
|
|
# $fh is being closed here, as we don't store it anywhere |
584 |
|
|
}); |
585 |
|
|
} |
586 |
|
|
|
587 |
|
|
# Some::function might look like this - all parameters passed before fork |
588 |
|
|
# and after will be passed, in order, after the communications socket. |
589 |
|
|
sub Some::function { |
590 |
|
|
my ($fh, $str1, $str2, $fh1, $fh2, $str3) = @_; |
591 |
|
|
|
592 |
|
|
print scalar <$fh>; # prints "hi 1\n" and "hi 2\n" |
593 |
|
|
} |
594 |
|
|
|
595 |
root |
1.4 |
=cut |
596 |
|
|
|
597 |
|
|
sub run { |
598 |
|
|
my ($self, $func, $cb) = @_; |
599 |
|
|
|
600 |
|
|
$self->[0] = $cb; |
601 |
root |
1.9 |
$self->_cmd (r => $func); |
602 |
root |
1.4 |
} |
603 |
|
|
|
604 |
root |
1.1 |
=back |
605 |
|
|
|
606 |
root |
1.8 |
=head1 PORTABILITY NOTES |
607 |
|
|
|
608 |
root |
1.10 |
Native win32 perls are somewhat supported (AnyEvent::Fork::Early is a nop, |
609 |
|
|
and ::Template is not going to work), and it cost a lot of blood and sweat |
610 |
|
|
to make it so, mostly due to the bloody broken perl that nobody seems to |
611 |
|
|
care about. The fork emulation is a bad joke - I have yet to see something |
612 |
|
|
useful that you cna do with it without running into memory corruption |
613 |
|
|
issues or other braindamage. Hrrrr. |
614 |
|
|
|
615 |
|
|
Cygwin perl is not supported at the moment, as it should implement fd |
616 |
|
|
passing, but doesn't, and rolling my own is hard, as cygwin doesn't |
617 |
|
|
support enough functionality to do it. |
618 |
root |
1.8 |
|
619 |
root |
1.1 |
=head1 AUTHOR |
620 |
|
|
|
621 |
|
|
Marc Lehmann <schmorp@schmorp.de> |
622 |
|
|
http://home.schmorp.de/ |
623 |
|
|
|
624 |
|
|
=cut |
625 |
|
|
|
626 |
|
|
1 |
627 |
|
|
|