trusty (3) System::Command::Reaper.3pm.gz

Provided by: libsystem-command-perl_1.107-1_all bug

NAME
       System::Command::Reaper - Reap processes started by System::Command


VERSION
       version 1.107


SYNOPSIS
       This class is used for internal purposes.  Move along, nothing to see here.


DESCRIPTION
       The System::Command objects delegate the reaping of child processes to System::Command::Reaper objects.
       This allows a user to create a System::Command and discard it after having obtained one or more
       references to its handles connected to the child process.

       The typical use case looks like this:

           my $fh = System::Command->new( @cmd )->stdout();

       The child process is reaped either through a direct call to "close()" or when the command object and all
       its handles have been destroyed, thus avoiding zombies (which would be reaped by the system at the end of
       the main program).

       This is possible thanks to the following reference graph:

               System::Command
                |   |   |  ^|
                v   v   v  !|
               in out err  !|
               ^|  ^|  ^|  !|
               !v  !v  !v  !v
           System::Command::Reaper

       Legend:
           | normal ref
           ! weak ref

       The System::Command::Reaper object acts as a sentinel, that takes care of reaping the child process when
       the original System::Command and its filehandles have been destroyed (or when System::Command "close()"
       method is being called).


METHODS
       System::Command::Reaper supports the following methods:

   new( $command )
       Create a new System::Command::Reaper object attached to the System::Command object passed as a parameter.

   close()
       Close all the opened filehandles of the main System::Command object, reaps the child process, and updates
       the main object with the status information of the child process.

       "DESTROY" calls "close()" when the sentinel is being destroyed.

   is_terminated()
       Returns a true value if the underlying process was terminated.

       If the process was indeed terminated, collects exit status, etc.


AUTHOR
       Philippe Bruhat (BooK), "<book at cpan.org>"


ACKNOWLEDGEMENTS
       This scheme owes a lot to Vincent Pit who on #perlfr provided the general idea (use a proxy to delay
       object destruction and child process reaping) with code examples, which I then adapted to my needs.


       Copyright 2010-2013 Philippe Bruhat (BooK), all rights reserved.


LICENSE
       This program is free software; you can redistribute it and/or modify it under the same terms as Perl
       itself.