Usage of \b and \r in C

Question

\b and \r are rarely used in practice. I just found out that I misunderstood these two escape sequences. A simple test:

printf("foo\bbar\n"); 

I expected it to output fobar, because \b will backspace the cursor, and b will overwrite the second o, but instead it outputs: foobar

The same is with \r:

printf("foo\rbar\n"); 

I thought \r will move the cursor to the beginning of the current line, so bar will replace foo, so the final output should be bar. However, it actually outputs:

foo bar 

Answer 1

The characters will get send just like that to the underlying output device (in your case probably a terminal emulator).

It is up to the terminal's implementation then how those characters get actually displayed. For example, a bell (\a) could trigger a beep sound on some terminals, a flash of the screen on others, or it will be completely ignored. It all depends on how the terminal is configured.