Why does the message print twice?

Question

I am creating a simple Tic Tac Toe for C, and here is a particular function which I am having a problem with. This is supposed to let the user select \'X\' or \'O\', and fo

Answer 1

It's because when you use getchar it returns the next character, but leaves the newline in the input buffer. So the next getchar returns that newline.

You should also be careful because getchar actually returns an int and not a char.

You can solve this either by another getchar, or use scanf like this:

scanf("%c ", &user);

Note the space after the c in the above format, it tells scanf to read and disregard trailing whitespace.

You could also read a line with e.g. fgets and then use a simple sscanf on that line, then no extra space is needed.