C - printf() not working but puts() is working fine

Question

void read_class_information(head* beginning, int scale_type) {
    puts(\"hello\");
    // printf(\"hello\");
}

I have a simple function called by main

Answer 1

Because printf() does not flush the output stream automatically. On the other hand puts() adds a new line '\n' at the end of the passed string. So it's working because the '\n' flushes de stdout.

Try

printf("hello\n");

Or, explicitly flush stdout

fflush(stdout);

right after the printf() statement.