Your program works fine for me when I run a Perl script for the child. 

my $pid = open2($JSREAD, $JSWRITE, q{perl -e"{ $_=<>; last if /^END$/;
+ ++$i; $m=qq{$i: $_}; warn $m; print $m; redo}"});

[download]

(The $|=1 isn't even necessary!)

Seems to me the problem is in the js side. But I doubt it's in readline. Are you sure your Perl script reaches END? Are you sure END is causing the child to exit?

By the way, you're adding newlines where they already exist in two different places.

In reply to Re^3: Diagnosing blocking io (or: finding the WHY of my Open2 woes). by ikegami
in thread Diagnosing blocking io (or: finding the WHY of my Open2 woes). by Socrates

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