RecordLayer.tryWriteRecord

TlsProgress tryWriteRecord(ContentType contentType,  ProtocolVersion ver,
          const(ubyte)[]  fragment)

Attempts to write a TLS record to the transport.

Serializes the record into the internal write buffer and attempts to flush it. Returns TlsProgress.DONE when the entire record has been written, TlsProgress.NEED_WRITE when the transport cannot accept more data, or TlsProgress.ERROR on failure.

Must not be called while a previous write is pending (check hasPendingWrite() first).

Parameters

`contentType`	The record content type.
`ver`	The protocol version for the header.
`fragment`	The record payload.

Returns

Progress indicator for the operation.