System Topic
You can use the System Topic item to locate information about the system. For example, you can use the item to see which sessions are currently in use. To request any of the following, use the Request command.
The System Topic supports the following:
Formats—Returns the name of the DDE formats supported. Always returns "Text".
Profiles—Returns the list of defined profile names. Each item is separated by a carriage return character (0x0D).
Session Started—Returns the topic letter for the session last started with the Start Session EXECUTE command.
SysItems—Returns the list of system items that you can request. Each item is separated by a carriage return character (0x0D).
Topics—Returns the list of system topics that are currently available for conversations. Each item is separated by a carriage return character (0x0D).