NAME

       Sympa::Process - Process of Sympa

SYNOPSIS

         use Sympa::Process;
         my $process = Sympa::Process->instance;
         $process->init(pidname => 'sympa');

         $process->daemonize;

         $process->fork;

DESCRIPTION

       Sympa::Process implements the class to handle process itself of Sympa software.

   Signal handling
       Once Sympa::Process is loaded, "SIGCHLD" signals are captured, and only defunct child
       processes invoked by fork() method are reaped.

   Methods
       instance ( )
           Constructor.  Creates a singleton instance of Sympa::Process object.

           Returns:

           A new Sympa::Process instance, or undef for failure.

       init ( key => value, ... )
           Instance method.  TBD.

       daemonize ( )
           Instance method.  Daemonizes process itself.  Process is given new process group,
           detached from TTY and given new process ID.

           Parameters:

           None.

           Returns:

           None.

       fork ( [ $tag ] )
           Instance method.  Forks process.  Note that this method should be used instead of
           fork() in Perl core.

           Parameter:

           $tag
               A string to determine new child process.  By default the name of calling process.

           Returns:

           See "fork" in perlfunc.

       reap_child ( [ blocking => 1 ] )
           DEPRECATED.

       wait_child ( )
           Instance method.  Waits for any child process.

           Parameters:

           None.

           Returns:

           0.  Returns "-1" on failure.

       sync_child ( [ hash => \%hash ], [ file => 1 ] )
           Updates process information in external data.

           Parameters:

           hash => \%hash
               Syncs PIDs in local map %hash

           file => 1
               Syncs child PIDs in PID file.  If dead PID is found, notification will be sent to
               super-listmaster.

           Returns:

           None.

       remove_pid ([ pid => $pid ], [ final => 1 ] )
           Instance method.  Removes process ID from PID file.  Then if the file is empty, it
           will be removed.

       write_pid ( [ initial => 1 ], [ pid => $pid ] )
           Instance method.  Writes or adds process ID to PID file.

           Parameters:

           initial => 1
               Initializes PID file.  If the file remains, notification will be sent to super-
               listmaster.

           pid => $pid
               Process ID to be written.  By default PID of current process.

       direct_stderr_to_file ( )
           Instance method.  TBD.

   Attributes
       Sympa::Process instance may have following attributes:

       {children}
           Hashref with child PIDs forked by fork() method as keys.

       {detached}
           True value is set if daemonize() method was called and the process has been detached
           from TTY.

       {generation}
           Generation of process.  If fork() method succeeds, it will be increased by child
           process.

   Utility functions
       eval_in_time ( $subref, $timeout )
           Evaluate subroutine $subref in $timeout seconds.

           TBD.

       register_handler ( )
           Registers "SIGCHLD" handler.  This function is usually called automatically during
           initialization.

HISTORY

       Sympa::Tools::Daemon appeared on Sympa 6.2a.41.

       Renamed Sympa::Process appeared on Sympa 6.2.12 and began to provide OO interface.

       Sympa 6.2.13 introduced daemonize() method and {detached} attribute.

       As of Sympa 6.2.14, "SIGCHLD" signal was captured and child processes were reaped
       immediately.  reap_child() method (formerly reaper()) was deprecated.