If this member is set to a value other than None it should point
to a function accepting a single argument (the connection
object). This will make all connection object methods work
asynchronously, with the callback routine being called upon
For reasons beyond my understanding, the callback routine
is currently never called. You are advised against using asynchronous
calls for the time being.
Write buf to channel chan, aborting after timeout
seconds. When eom has the value cmFlagsEOM, an
end-of-message indicator will be written after the data (if this
concept has a meaning for this communication tool). The method returns
the number of bytes written.
Set the configuration string for the tool. The strings are parsed
left-to-right, with later values taking precedence. This means
individual configuration parameters can be modified by simply appending
something like 'baud 4800' to the end of the string returned by
GetConfig() and passing that to this method. The method returns
the number of characters actually parsed by the tool before it
encountered an error (or completed successfully).
Present the user with a dialog to choose a communication tool and
configure it. If there is an outstanding connection some choices (like
selecting a different tool) may cause the connection to be
aborted. The return value (one of the choose* constants) will