Redis 02: RESP, The Wire Protocol

The label that lets a stranger’s bytes say, before you read a single one of them, exactly how many there are.

Before you start. You need to be able to count the characters in a word and add two small numbers - that’s the whole of the arithmetic here. The toy so far is a program that listens on a network connection (a socket: one open line between two programs, carrying bytes both ways), reads one line of text at a time and answers it, and it only works today because whoever is typing presses Enter after every word, the way a person would, not a program.