How Do Sockets Work in C?

Question

I am a bit confused about socket programming in C.

You create a socket, bind it to an interface and an IP address and get it to listen. I found a couple of web resources

Answer 1

When you do a read on the socket, you tell it how many maximum bytes to read, but if it doesn't have that many, it gives you however many it's got. It's up to you to design the protocol so you know whether you've got a partial packet or not. For instance, in the past when sending variable length binary data, I would put an int at the beginning that said how many bytes to expect. I'd do a read requesting a number of bytes greater than the largest possible packet in my protocol, and then I'd compare the first int against however many bytes I'd received, and either process it or try more reads until I'd gotten the full packet, depending.