low-level network connection type to provide asynchronous I/O (library)

 The socket package provides a low-level network connection type which
 integrates with Go's runtime network poller to provide asynchronous I/O and
 deadline support.
 .
 This package focuses on UNIX-like operating systems which make use of
 BSD sockets system call APIs. It is meant to be used as a foundation for
 the creation of operating system-specific socket packages, for socket
 families such as Linux's AF_NETLINK, AF_PACKET, or AF_VSOCK. This package
 should not be used directly in end user applications.
 .
 Any use of package socket should be guarded by build tags, as one would
 also use when importing the syscall or golang.org/x/sys packages.