The ReuseDDElParam function allows an application to reuse a packed DDE lParam parameter, rather than allocating a new packed lParam. Using this function reduces reallocations for applications that pass packed DDE messages.
LONG ReuseDDElParam(
LONG lParam, // posted lParam to be reused
UINT msgIn, // identifier of received message
UINT msgOut, // identifier of posted message
UINT uiLo, // low-order word of new lParam
UINT uiHi // high-order word of new lParam
);
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero.
The return value must be posted as the lParam parameter of a DDE message; it must not be used for any other purpose. Once the return value is posted, the posting application need not perform any action to dispose of the lParam parameter.
Use ReuseDDElParam instead of FreeDDElParam if the lParam parameter will be reused in a responding message. ReuseDDElParam returns the lParam appropriate for reuse.
This function allocates or frees lParam parameters as needed, depending on the packing requirements of the incoming and outgoing messages. This reduces reallocations in passing DDE messages.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in dde.h.
Import Library: Use user32.lib.
Dynamic Data Exchange Overview, Dynamic Data Exchange Functions, FreeDDElParam, PackDDElParam, UnpackDDElParam