Why does my output only print if there is another print after it?

Question

Interesting little bug here:

if (host != NULL) {
    printf("hi");
} else {
    printf("FAIL");
}
return 0;

doesn\'t prin

Answer 1

The difference is the \n characters.

As you printf characters, they are accumulated in a buffer which isn't sent to the output device until an 'end of line' character is sent.