To be a valid TCP packet, it needs to contain at a minimum a 20-byte IP header and a 20-byte TCP header, plus the one byte of payload. In practice your server is probably receiving the packet over Ethernet, so it probably has an Ethernet header and things like that, too, but that's a minimum. You could approach it over, say, SLIP.
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To be a valid TCP packet, it needs to contain at a minimum a 20-byte IP header and a 20-byte TCP header, plus the one byte of payload. In practice your server is probably receiving the packet over Ethernet, so it probably has an Ethernet header and things like that, too, but that's a minimum. You could approach it over, say, SLIP.