samr7/vanitygen — reverse-engineered prompt

Build me a fast standalone command line vanity address generator in C for Bitcoin style addresses. I want to type a prefix like 1Love and have the tool keep generating keys until it finds an address that matches, then print the pattern, address, and private key.

It should show useful progress while it runs, like keys checked per second, total checked, probability, and rough time estimates. It should support normal Bitcoin addresses, testnet addresses, and Namecoin addresses. Let users search exact prefixes, optionally ignore letter case, or use regular expression patterns. Also let them pass many patterns directly, from a file, or from standard input.

Please make it use all CPU cores by default, with an option to limit the number of worker threads. It should validate impossible prefixes, estimate difficulty before starting, and be buildable from source on Linux, with Windows support if practical. Keep the interface simple and include a README with examples.