Re: subprocesses lifecycle

Eric Pozharski <whynot@xxxxxxxxxxxxxx> wrote:

And what surprises me most is that, as Hans Mulder discovered, lexical
filehandles are waited, globals are not. Wouldn't someone willing to dig
through source and explain why that's that way?

I am guessing it is because lexicals are destroyed when they go out of
scope, while globals are only destroyed during "global destruction", during
which time the automatic waiting behavior may not be working.

If one uses circular refs to prevent a lexical filehandle from going out of
scope until global destruction, they don't wait. For example,
the below exits immediately:

perl -le ' my @y; open $y[0], "sleep 5 |" or die; push @y,\@y'

Sometimes it waits anyway. Global destruction is hard to predict.
This waits:

perl -le ' my @y; open $y[0], "sleep 5 |" or die; push @y,\@y; $z=bless {}'


Xho

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