How to trace a raw (character) device stream on Unix ?

Posted by Fabien on Stack Overflow See other posts from Stack Overflow or by Fabien
Published on 2010-05-03T03:05:47Z Indexed on 2010/05/03 3:18 UTC
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unix

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daemon

I'm trying to trace what is transiting in a raw (character) device on an Unix system (ex: /dev/tty.baseband) for DEBUG purpose.

I am thinking of creating a deamon that would:

upon start rename /dev/tty.baseband to /dev/tty.baseband.old.
create a raw node /dev/tty.baseband
spawn two threads:
Thread 1: reading /dev/tty.baseband.old writing into /dev/tty.baseband
Thread 2: reading /dev/tty.baseband writing into /dev/tty.baseband.old

This would work a little bit like a MITM process. I wonder if there is not a 'standard' way to do this.

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