tunneling io of a running process



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tunneling io of a running process

Postby nir m » Wed, 06 Dec 2006 22:25:17 GMT

I have a process which runs in a system and has a thread that takes
input and prints output to the terminal.
However it is not being run from a terminal so it is not connected to
any tty device.
What I want to acheive  is to be able to somehow connnect to this
process' stdin/stdout at some point and interact with it (after it has
been running for sometime).
When I started thinking about it my first thought was using 2 named
pipes and select() calls with timeouts, and interact with it through
another process which will open those pipes.
It sort of works but it has all kinds of problems like deadlocks
between the two processes at some specific cases and so on. I guess I
can solve those specific problems but I'm sure there's a better way to
implement what I'm trying to do.

I've heard of pty's and even read the relevant chapter in advanced unix
programming but couldn't quite understand how to use it for my purpose.

could someone please outline how do I get this sort of thing to work
with pty's or, alternatively , provide me with another idea besides the
two i've already mentioned?

Additionally, for some reason, I can't find any real reference+examples
about pty's in the web so if
someone could point me to such reference, that would be great.
Btw it can be assumed that the code of the running process can be
changed to fit to any solution.

Thanks you,

Re: tunneling io of a running process

Postby tmstaedt » Sat, 09 Dec 2006 18:09:01 GMT

Well, just googled and found
 http://www.**--****.com/ ~ali/K0D/UNIX/PTY/. There is some sample


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