Today, while porting the MRY Print Spooler banner-page language processor to TOPS-20, I discovered that the KCC C Compiler does not support binary constants.

I really didn't want to re-code 4,600 lines of big-letter font C-headers.

So I added binary constants to KCC-6.   It was trivial.

$diff -C 7 tops20:<kcc-6.kcc>cclex.c cclex.c
*** dist:<kcc-6.kcc>cclex.c Sun Mar 6 23:58:24 2022
--- work:<kccdist.kcc-6.kcc>cclex.c Mon Mar 7 20:27:17 2022
***************
*** 288,301 ****
--- 288,306 ----
      if ((c = *cp) == '0') { /* Octal/Hex prefix? */
        c = *++cp;
        if (c == 'x' || c == 'X') { /* Hex (base 16) */
            while (isxdigit(c = *++cp)) {
                if (v & (017 << (TGSIZ_LONG-4))) ovfl++;
                v = ((unsigned long)v << 4) + toint(c);
            }
+       } else if (c == 'b' || c == 'B') { /* Binary (base 2) */
+           while (((c = *++cp) == '0' || c == '1')) {
+               if (v & (01 << (TGSIZ_LONG-1))) ovfl++;
+               v = ((unsigned long)v << 1) + toint(c);
+           }
        } else { /* Octal (base 8) */
            while (isodigit(c)) {
                if (v & (07 << (TGSIZ_LONG-3))) ovfl++;
                v = ((unsigned long)v << 3) + c - '0';
                c = *++cp;
            }
        if (isdigit(c)) { /* Helpful msg for common error */