Intercept data on serial port

[pfrossard]

Hello,
I dont know if this is the right forum,
But I try to find a solution,
I want to intercept data from/to serial port without disrupting the software that manages the serial port,
(I would like to save the data to a file or sent into a socket)
I searched somes modules and programs (linspy, ttysniff, interceptty, maxty ...),
A bit complicated (There are some diff. between kernel 2.4 and 2.6),
So I'd like to change the serial port driver to intercept the "read" and "write " and do what I want with the data,
I'd like to know what do you think about this and may be another solution ...
Thanks.

[Rubberman]

You could write a kernel module which could do this without changing the serial port driver itself (a VERY dangerous proposition). In any case, this will not be simple or easy to do, and there remains the possibility that you will mung the entire system - serial I/O is used extensively for just about anything you can think of - including I/O rediretion in shell scripts, etc.

[pfrossard]

Do you know where could I post for more informations about linux drivers ?
Thanks.

[Rubberman]

There are a number of sources such as The Linux Documentation Project, The Linux Kernel Archives, and O'Reilly's "Linux Device Drivers, 3rd Edition" which is available as a set of PDF files for free download. I have a copy, but I don't remember the exact URL that I downloaded it from. A google search should find it easily enough.