Buffering is done at the application level, not at the system level, so you can't control whether another application (ProFit) buffers its output or not. Even if it's your child.

Many applications (including perl), buffer STDOUT when it's not connected to a terminal. So the trick is to convince ProFit that it's connected to a terminal. That's where pseudo ttys come in.

In reply to Re: open3 buffering in linux vs. os x by ikegami
in thread open3 buffering in linux vs. os x by Lexicon

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