As others have noted, the 'In' looks like a rendering bug with whatever terminal emulator you're using. Otherwise it looks pretty normal: `fopen (const char *re

As others have noted, the 'In' looks like a rendering bug with whatever terminal emulator you're using. Otherwise it looks pretty normal: `fopen (const char *restrict filename, const char *restrict mode)` looks like a perfectly good C function, and (if you already know C) it's easy to see the parts that don't look like they belong.