/* PBXA64 handbook-style C text example: protocol_length_prefix.
 * parse a two-byte big-endian protocol length field. This source deliberately keeps every transformation visible
 * instead of hiding it behind library calls, making it useful for tracing.
 */
int main(void) {
    unsigned char header[] = { 0, 42, 80, 66 }; int length = ((int)header[0] << 8) | header[1]; int tag = ((int)header[2] << 8) | header[3]; return length == 42 && tag == 20546 ? 0 : 1;
}

/* Discussion: inspect the loop bounds, byte classification, and final return
 * value. The bounded-C frontend currently records CIR0200 for all C source;
 * this example remains a real handbook program for the public C surface once
 * that frontend gate is restored. */
