About recvfrom part I think I got the answer from
https://www.cs.cmu.edu/~srini/15-441/F01.full/www/assignments/P2/htmlsim_split/node12.html

"...In an actual UNIX system, socket descriptors are set to be non-blocking using fcntl() with type O_NONBLOCK, and Recvfrom() returns errno EWOULDBLOCK when there is no data to be read on the non-blocking socket"

—
Reply to this email directly or view it on GitHub.