Multiple Client Server Programming in C

Hey guys, so as it is mentioned in the title i'm making a multiple clients server program, until now, i can send and receive messages between client/server but I'm stuck at how to manipulate the data received from the client, for example i have a function that calculates a thing depending on what the client say, i tried to redirect STDOUT to the socket but I didn't get what I need, so pls if someone have done this kind of things before or have any idea how I can do it, tell me in the comments below ! :confused:

Thank you!

> i tried to redirect STDOUT to the socket but I didn't get what I need
Post your example of what didn't work.