proxysocket

Cross-platform C library to establish TCP connections using a proxy.
Supports different connection methods:
- no proxy (optionally allowing to bind to a local address and/or port)
- HTTP proxy: only CONNECT method, only without authentication or basic authentication
- SOCKS4: without IDENT functionality
- SOCKS5 (RFC 1928): only without authentication or username/password
Features:
- Currently only support IPv4 TCP connections.
- Returns a standard operating system SOCKET that can be manipulated by standard operating system functions like send() and recv().
- Supports daisy-chaining multiple proxies.
- Can also be used for direct connections (without proxy) optionally binding to a local address and/or port.