#include <dde.h>
WM_DDE_REQUEST
wParam = (WPARAM) hwnd; /* handle of posting window */
lParam = MAKELPARAM(cfFormat, aItem); /* clipboard format and item */A dynamic data exchange (DDE) client application posts a WM_DDE_REQUEST message to a DDE server application to request the value of a data item.
hwnd
Value of wParam. Identifies the sending window.
cfFormat
Value of the low-order word of lParam. Specifies a standard or registered clipboard format number.
aItem
Value of the high-order word of lParam. Specifies which data item is being requested from the server.
This message does not return a value.
Posting
The application posts the WM_DDE_REQUEST message by calling the PostMessage function, not the SendMessage function.
The application allocates aItem by calling the GlobalAddAtom function.
Receiving
If the receiving (server) application can satisfy the request, it responds with a WM_DDE_DATA message containing the requested data. Otherwise, it responds with a negative WM_DDE_ACK message.
When responding with either a WM_DDE_DATA or WM_DDE_ACK message, the application can reuse the aItem atom or delete it and create a new one.