BACKSLASH
case BACKSLASH:
*e_lab++ = BACKSLASH;
if (*p == BACKSLASH)
putc(BACKSLASH, output);
if (*e_token == BACKSLASH) { /* if escape, copy extra char */
*++e_token = BACKSLASH;
if (*buf_ptr == BACKSLASH)
*++e_token = BACKSLASH;