Like other languages output buffering takes place even in C. Output buffering will cause output of a program to appear in chunks after long intervals, instead of each line appearing the moment it is output. To disable output buffering a very strange piece of code has to be written which looks like this
//disable output buffering setvbuf(stdout, NULL, _IONBF, 0); printf('Hello');
Or call the fflush after every output
The above is for Linux.