Exit functions in C

Question

What is the difference between exit(), _exit() and _Exit() in C?

How do I decide which to use?

On bash, <

Answer 1

Normative in C99 are exit and _Exit.

The difference between the two is that exit also executes the handlers that may be registered with atexit and closes streams etc whereas _Exit doesn't call the atexit routines and may or may not close streams properly.

_exit is from POSIX and has similar properties as _Exit with the difference that it is guaranteed to close streams properly.

In summary, whenever you can you should use exit, this is the cleanest way to terminate.