DotTerminatedMessageWriter is a class used to write messages to a server that are terminated by a single dot followed by a <CR><LF> sequence and with double dots appearing at the begining of lines which do not signal end of message yet start with a dot. Various Internet protocols such as NNTP and POP3 produce messages of this type.

This class handles the doubling of line-starting periods, converts single linefeeds to NETASCII newlines, and on closing will send the final message terminator dot and NETASCII newline sequence.