the sysread always returns 0 bytes, with no warnings or errors.

But you're not checking for errors. 

      my $bytes = sysread($handle,$buf,1024);
      if ($bytes == 0) {

[download]
should be 
      my $bytes = sysread($handle,$buf,1024);
      die "sysread: $!" if !defined($bytes);
      if ($bytes == 0) {

[download]

You imply you have warnings turned on, in which case this won't help since you'd get "Use of uninitialized value in numeric eq (==)" on error.

In reply to Re: Yet another Open3 issue . . . or is it? by ikegami
in thread Yet another Open3 issue . . . or is it? by johnevi

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