The Export Data Command uses Dynamic Data Exchange (DDE) to export histogram data for import by MultiCycle for Windows 3.0 (Phoenix Flow Systems, San Diego, California).
Dynamic data exchange (DDE) is a form of interprocess communication that uses shared memory to exchange data between applications. Applications can use DDE for one-time data transfers and for ongoing exchanges in which the applications send updates to one another as new data becomes available.
Dynamic data exchange differs from the clipboard data-transfer mechanism that is also part of the Windows operating system. One difference is that the clipboard is almost always used as a one-time response to a specific action by the user--such as choosing the Paste command from a menu. Although DDE may also be initiated by a user, it typically continues without the user's further involvement. When the Enable Histogram Export item is selected in the File Preferences Dialog, WinMDI automatically sends updated histogram data via DDE whenever Open, Next and Prev Commands are issued.