getc()                       read input

    Reads and returns next character from current input file.  Returns 0 of
    end-of-file, -1 on error.

    Note:  If  the current input  file is the  standard input file  and the
    standard  input  file  has  not  been  piped  or re-directed, then this
    function, and 'getc', may return 0  when a function key, cursor key  or
    other key not corresponding to an ASCII character is pressed.  A sceond
    call must be made to read the keyboard scan code.