How to write a timer to monitor a socket server?

[licht]

I have a C++ program that uses unix domain socket in this way: Client A has a socket connection to Server B. A sends some data to B. B processes data and return results to A.

However, sometimes, B might take too long to process data and in such a case, for efficiency consideration, A would expect B to simply terminate the processing and notify A with a failure message other than waiting for ever. So, in B, I would like to write a timer T. It starts timing when B receives data from A. It would timeout if B spends some predefined length of time on processing the data. Then B will stop and sends some message back to A to let it know.

Any idea or suggestions for doing this? Thanks!

[cyberinstru]

Use select() call and FD_SETs for this.

[the_unforgiven]

Use select() call and FD_SETs for this.

If the server knows when to terminate the connection and there is a protocol for the communication, it could simply send a TERMINATE request/response (depending on how you look at it) to the client - which the client can honor by closing the socket. You don't need select() - however that is also an option if the server decides to terminate the connection without notifying the client.

@licht,
You already know what you want! So, what sort of help are you looking from us?

[cyberinstru]

You can check if you have rcvd data to any descriptor using FD_ISSET.... so based on that u can proceed... or else, how do u know, if you r rvng data or not...

May be i am not aware of the other way around to know that... cud u plz brief the_unforgiven?