The binary IPC protocol is super simple. Aside from the initial 0x00/0x01 handshake, this is the message format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------------------------------------------------------+
| Payload length (32) |
+---------------------------------------------------------------+
| Payload data |
+ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +
| Payload data continued... |
+---------------------------------------------------------------+
Payload length: 32 bits
32-bit big-endian unsigned integer, indicating the length of the payload data, in bytes.
Payload data: x bytes
Binary data message. Data cannot exceed MAX_LENGTH bytes, determined in lib/ProtocolStream.js (typically 2147483647 - 4 bytes on 64-bit systems).