C程序中奇怪的输出

Question

So I am just starting to learn C, I am using gcc if that makes any difference, and for some reason this simple program is giving me weird output:

    #include <stdio.h>

    main()
    {
        int c;

        while (c == getchar() != EOF)
        {   
            putchar(c);
        }   
     }

I save it and use :!gcc % then :!./a.out in vim, when I type in any letter then Enter, it just gives me "^^" as the output. I searched around and couldn't find anyone else with this problem, and it's copied straight out of K&R so I don't know what could be causing this error, does anyone know what's going on?

Answer 1

Ned Stark's answer is right, I had 2 equals signs and that's what was causing the weird errors. Thanks for all the help guys! Ned, if you want to post an answer I'll mark yours as correct, otherwise I'll mark this as correct in two days.