It's been a while since I looked at doing this, but IIRC it's fairly
dependent on the processing model that Apache is using. Are you
mpm_prefork, or mpm_worker?
Also, I found it was important to redirect stderr to /dev/null:
sub play {
system "/usr/bin/xmms -t 2> /dev/null";
}
On Tue, Jan 3, 2012 at 12:48 PM, David Booth <da...@dbooth.org> wrote:
> I am trying to run a shell command from a mod_perl2 response handler.
> It works properly for some number of HTTP requests, but sometimes it
> fails (somewhat randomly) and I see in my Apache2 error log that one of
> the Apache2 child processes has died with a segmentation fault.
> For example, /var/log/apache2/error.log shows:
>
> [Tue Jan 03 12:16:10 2012] [notice] child pid 3538 exit signal Segmentation
> fault (11)
>
> Is this normal? How does one normally run a shell command from a
> response handler? I do not want to return the command's output to the
> client.
>
> Here is a trivial example response handler that exhibits this behavior:
>
> sub handler
> {
> my $r = shift || die;
> my $f = $ENV{DOCUMENT_ROOT} . "/date.txt";
> system("date >> $f");
> $r->internal_redirect("/date.txt");
> return Apache2::Const::OK;
> }
>
> Can anyone provide any guidance? Does this work for you?
>
> Note that you may not notice the problem if you don't carefully watch
> the Apache2 error log (e.g., with "tail -f /var/log/apache2/error.log"),
> because Apache2 automatically spawns new children processes as needed,
> and client (such as Firefox or wget, though not curl) seem to
> automatically re-try the request when it fails, thus giving the illusion
> of succeeding.
>
> P.S. I have posted about this on perlmonks, but thus far have not found
> a solution:
> http://www.perlmonks.org/?node_id=945947
>
>
> --
> David Booth, Ph.D.
> http://dbooth.org/
>
> Opinions expressed herein are those of the author and do not necessarily
> reflect those of his employer.
>
