Use "<&".fileno($out_fh1) as $in_fh2. Also open cmd3.log on a filehandle, and pass that in as the err_fh to each command in sequence.

Untested, but the documentation indicates that that should work.

In reply to Re: Robustly piping several processes. by Anonymous Monk
in thread Robustly piping several processes. by BazB

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