What happened when we do not include '\0' at the end of string in C?

Question

In C, when I initialize my array this way:

char full_name[] = {
    \'t\', \'o\', \'a\', \'n\'
};

and print it with printf(\"%s\", fu

Answer 1

If you use a non-null-terminated char sequence as a string, C functions will just keep going. It's the '\0' that tells them to stop. So, whatever happens to be in memory after the sequence will be taken as part of the string. This may eventually cross a memory boundary and cause an error, or it may just print gibberish if it happens to find a '\0' somewhere and stop.