What is meant by “blocking system call”?

Question

What is the meaning of \"blocking system call\"?

In my operating systems course, we are studying multithreaded programming. I\'m unsure what is meant when I read in my t

Answer 1

A blocking system call is one that must wait until the action can be completed. read() would be a good example - if no input is ready, it'll sit there and wait until some is (provided you haven't set it to non-blocking, of course, in which case it wouldn't be a blocking system call). Obviously, while one thread is waiting on a blocking system call, another thread can be off doing something else.