I am hopeing that somebody can add some clarity to this old thread. Can somebody tell me why the following coded hangs if the line which defines the @outlines array is commented out?

I have used open3 in other places w/o reading the the child's output and the process didn't hang. I expect it is because in that case the command didn't have output.

I understand how some of the other example programs in this thread prevent locking while read from open3's handles but it seems strange that this would lock when I am not reading from them and just calling waitpid as soon as possible.

Also, should I explicitly close $wtr, $rtr, and $err?

...
my($wtr,$rdr);
my $err = gensym;

### $logcmd is a command that returns approx. 460 lines.
my $pid = open3($wtr, $rdr, $err, "$logcmd");
my @outlines = <$rdr>;  ### if this line is commented out we hang on w
+aitpid
waitpid( $pid, 0 );
...

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In reply to Re^2: IPC::Open3 woes by LNEDAD
in thread IPC::Open3 woes by BazB

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