Closing socket, what's the expected behavior

[RobinK]

Let's say I opened a TCP socket to another server. I have two threads, in one thread I do a block read(...), while in the 2nd thread I close the socket. what would be the expected behavior of my 1st thread?

I am asking this because I saw different behavior on different builds, on one redhat version the 1st thread return with a 0, indicate the socket is closed, on another version the 1st thread got stuck and never return from read().

Many thanks in advance!

[Rubberman]

Great question! I think this is implementation-defined. In theory, it can either return 0, and have either the eof or bad bits set, or it can return -1, and set errno appropriately. I think you need to check for both situations for a cross-platform implementation.