TcpConnectionState.sendFile

SendStatus sendFile(HANDLE fileHandle, ulong offset, size_t count) @trusted nothrow

Send a file over the connection using zero-copy TransmitFile.

`fileHandle`	Win32 file handle. Ownership transfers to the connection.
`offset`	Byte offset to start sending from.
`count`	Number of bytes to send (0 = entire file from offset).

SendStatus indicating success or failure.