We have a PSGI/Plack service (no Dancer nor Mojo involved, just StarMan) and it daemonizes a child in order to finish some processing that we don't want to cause a delay in the response. We had to daemonize as just fork()ing and exec()ing still left the parent process waiting before finishing the response. I didn't take the time to investigate why.

But testing showed that standard daemonization was sufficient. Note that we chose to exec() from the beginning as not exec()ing has risk of leaving objects alive that might cause problems, especially when the child finishes (and the objects try to finish their work).

We send the data needed for the finalization work as JSON written through a pipe to the child's STDIN: 

open( my $worker, '|-', $ASYNC_NOTIFIER ) or die ...;

[download]

And the child daemonizes after it finishes reading STDIN.

- tye        

In reply to Re: How to fork in PSGI/Dancer2 (daemonize) by tye
in thread How to fork in PSGI/Dancer2 by morgon

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