Re update 2,

chomp returns what it chomped, if anything. Since the string doesn't end with a newline (the content of $/), chomp returns an empty string or something equally false.

So adjust $/ if you want to chomp something other than newlines. But even then, it makes no sense to check what chomp returns. Use

chomp($out), print "Output: $out\n" if $out;
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or the saner

if ($out) { chomp($out); print "Output: $out\n"; }
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Actually, why is the chomp conditional?

chomp($out);
print "Output: ", length($out) ? $out : "[nothing]", "\n";
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