"IO::Async::PID" - event callback on exit of a child process

       Paul Evans <leonerd@leonerd.org.uk>

perl v5.40.1                                       2025-05-17                                IO::Async::PID(3pm)

       This subclass of IO::Async::Notifier invokes its callback when a process exits.

       For most use cases, a IO::Async::Process object provides more control of setting up the process,
       connecting filehandles to it, sending data to and receiving data from it.

       The following events are invoked, either using subclass methods or CODE references in parameters:

   on_exit$exitcode
       Invoked when the watched process exits.

pid
          $process_id = $pid->pid;

       Returns the underlying process ID

   kill
          $pid->kill( $signal );

       Sends a signal to the process

       "IO::Async::PID" - event callback on exit of a child process

       The following named parameters may be passed to "new" or "configure":

   pid=>INT
       The process ID to watch. Must be given before the object has been added to the containing IO::Async::Loop
       object.

   on_exit=>CODE
       CODE reference for the "on_exit" event.

       Once the "on_exit" continuation has been invoked, the "IO::Async::PID" object is removed from the
       containing IO::Async::Loop object.

          use IO::Async::PID;
          use POSIX qw( WEXITSTATUS );

          use IO::Async::Loop;
          my $loop = IO::Async::Loop->new;

          my $kid = $loop->fork(
             code => sub {
                print "Child sleeping..\n";
                sleep 10;
                print "Child exiting\n";
                return 20;
             },
          );

          print "Child process $kid started\n";

          my $pid = IO::Async::PID->new(
             pid => $kid,

             on_exit => sub {
                my ( $self, $exitcode ) = @_;
                printf "Child process %d exited with status %d\n",
                   $self->pid, WEXITSTATUS($exitcode);
             },
          );

          $loop->add( $pid );

          $loop->run;