[ excerpt from developer's web site ]

This is C++ class library wrapping the Berkeley
sockets C API, and therefore works on most Unixes and also Win32.
Features include, but are not limited to, SSL support, IPv6 support,
TCP and UDP sockets, encrypted TCP, HTTP protocol, highly customizable
error handling.
The source code is released under the terms of the GNU GPL, but is
also available under an alternative license.