Buffering


Many problems you find are related to buffering issues
A file can be _IONBF, _IOLBF, _IOFBF
With setvbuf(3) you can change the set up
stdout is usually _IOLBF
stderr is usually _IONBF
if you open files with fopen(3), you get _IOFBF

We must also remember that a tty is special
The tty is managed by a line discipline
Normally, it has a line buffer too
tcgetattr(3) and tcsetattr(3) work on tty settings