App::Chart::Gtk2::Subprocess -- child process to run jobs
use App::Chart::Gtk2::Subprocess; my $subprocess = App::Chart::Gtk2::Subprocess->new;
App::Chart::Gtk2::Subprocess is a child sub-process running
chart --subprocess. That subprocess reads tasks from its standard input (in a length-delimited "Storable" format) and prints messages and
PerlIO::via::EscStatus status strings to its stdout. The
App::Chart::Gtk2::Subprocess sends a
App::Chart::Gtk2::Job task to the subprocess then reads its output.
App::Chart::Gtk2::Subprocess notices if the child dies because the output pipe closes. It then waits that child with
Glib::Child->watch_add is not used because in single thread mode it's implemented with a non-restart
sigaction to stop the main loop poll, and it's a bit worrying to think how much third-party library code might not cope gracefully with EINTR.
Create and return a new subprocess. The process is running, but idle.
$subprocess must be idle. This is meant for use by
Return the process ID of
$subprocess, or undef if no longer running.
Forcibly stop the process and any job running in it.