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the putchar function

johnmerlino (110)
I understand the below program, except when EOF is reached and the state is SLASH, then it does something with the putchar function. I thought the putchar function just puts a character to terminal, but in this example, I don't understand all those parameters passed to it:

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#include <stdio.h>

int
 main(void)
{
    /* State machine's current state. */
    enum {
        PROGRAM,
        SLASH,
        COMMENT,
        STAR,
        QUOTE,
        LITERAL
    } state;

    /* If state == QUOTE, then ' or ".  Otherwise, undefined. */
    int quote;

    state = PROGRAM;
    for (;;) {
        int c = getchar();
        if (c == EOF) {
            if (state == SLASH)
                putchar('/' //**/
                        1 / 1 /'\1');
            break;
        }

        switch (state) {
        case SLASH:
            /* Program text following a slash. */
            if (c == "/*"[1]) {
                state = COMMENT;
                break;
            }
            putchar('/');
            state = PROGRAM;
            /* Fall through. */

        case PROGRAM:
            /* Program text. */
            if (c == '\'' || c == '"') {
 // Note \' is escaping the single quote '
                quote = c;
                state = QUOTE;
                putchar(c);
            }
            else if (c == "/*"[0])
                state = SLASH;
            else
                putchar(c);
            break;

        case COMMENT:
            /* Comment. */
            if (c == '*')
                state = STAR;
            break;

        case STAR:
            /* Comment following a star. */
            if (c == '/')
                state = PROGRAM;
            else if (c != '*') {
                state = COMMENT;
                putchar (' ');
            }
            break;

        case QUOTE:
            /* Within quoted string or character constant. */
            putchar(c);
            if (c == '\\')
 // this checks for a single backslash (because the backslash has to be escaped with another backslash)
                state = LITERAL;
            else if (c == quote)
                state = PROGRAM;
            break;

        case LITERAL:
            /* Within quoted string or character constant, following \. */
            putchar(c);
            state = QUOTE;
            break;

        default:
            abort();
        }
    }

    return 0;
}


This part is what I don't understand:

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                putchar('/' //**/
                        1 / 1 /'\1');
kbw (9488)
It looks like an error to me.
Smac89 (1727)
It is just simply division, by a lot of 1's. This is what it is supposed to look like:

putchar('/' / /**/ 1 / 1 /'\1');

Notice the division now?
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