You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@perl.apache.org by Jasper Zhao <jz...@cidc.com> on 2011/07/13 22:08:40 UTC
[mp2] To get APR::Pool::cleanup_for_exec officially supported
Dear mod_perl2 Developers,
As you know when you want to spawn a sub-process and execute an external program you can use 'spawn_proc_prog' defined in Apache2::SubProcess. However, if you want to spawn a sub-process and call a Perl subroutine, the sub-process won't release the listening port therefore you cannot restart your httpd daemon if the spawned process is still running.
APR::Pool::cleanup_for_exec comes to rescue. It does some cleanup tasks including releasing the listening port. See the code snippet below. The method works properly. However in the mp2 document at the link below, it says this method is an unsupported API. Is it possible to get it officially supported?
http://perl.apache.org/docs/2.0/api/APR/Pool.html#C_cleanup_for_exec_
sub fork_and_call_sub
{
my $pid = fork();
if(!defined $pid) {
die("Cannot fork: $!")
}
if($pid) {
#Parent process
return;
}
# Child goes here
close STDIN;
close STDOUT;
open STDIN, '/dev/null';
open STDOUT,'>/dev/null';
setsid;
APR::Pool::cleanup_for_exec();
call_time_consuming_method();
CORE::exit(0);
}
Jasper
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@perl.apache.org
For additional commands, e-mail: dev-help@perl.apache.org
Re: [mp2] To get APR::Pool::cleanup_for_exec officially supported
Posted by Fred Moyer <fr...@redhotpenguin.com>.
I looked at this a while back but haven't had the tuits to follow up
on it. Patches welcome :)
On Wed, Jul 13, 2011 at 1:08 PM, Jasper Zhao <jz...@cidc.com> wrote:
> Dear mod_perl2 Developers,
>
> As you know when you want to spawn a sub-process and execute an external program you can use 'spawn_proc_prog' defined in Apache2::SubProcess. However, if you want to spawn a sub-process and call a Perl subroutine, the sub-process won't release the listening port therefore you cannot restart your httpd daemon if the spawned process is still running.
>
> APR::Pool::cleanup_for_exec comes to rescue. It does some cleanup tasks including releasing the listening port. See the code snippet below. The method works properly. However in the mp2 document at the link below, it says this method is an unsupported API. Is it possible to get it officially supported?
> http://perl.apache.org/docs/2.0/api/APR/Pool.html#C_cleanup_for_exec_
>
> sub fork_and_call_sub
> {
> my $pid = fork();
> if(!defined $pid) {
> die("Cannot fork: $!")
> }
> if($pid) {
> #Parent process
> return;
> }
> # Child goes here
> close STDIN;
> close STDOUT;
> open STDIN, '/dev/null';
> open STDOUT,'>/dev/null';
>
> setsid;
> APR::Pool::cleanup_for_exec();
> call_time_consuming_method();
> CORE::exit(0);
> }
>
> Jasper
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: dev-unsubscribe@perl.apache.org
> For additional commands, e-mail: dev-help@perl.apache.org
>
>
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@perl.apache.org
For additional commands, e-mail: dev-help@perl.apache.org