usr/src/lib/libc/stdio/mktemp.c

/*      mktemp.c        4.1     83/06/22        */

char *
mktemp(as)
char *as;
{
        register char *s;
        register unsigned pid;
        register i;

        pid = getpid();
        s = as;
        while (*s++)
                ;
        s--;
        while (*--s == 'X') {
                *s = (pid%10) + '0';
                pid /= 10;
        }
        s++;
        i = 'a';
        while (access(as, 0) != -1) {
                if (i=='z')
                        return("/");
                *s = i++;
        }
        return(as);
}