You are opening a pipe that connects the STDOUT of /usr/bin/js to your SY handle. I'd expect /usr/bin/js to write errors to its STDERR.

Either open a pipe to its STDERR (for instance, by using IPC::Open3, or by first redirecting the STDERR of /usr/bin/js to its STDOUT, using your shells syntax.

In reply to Re: perl, open and pipe by JavaFan
in thread perl, open and pipe by perlpreben

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