hwndHelpInstance (HWND) - input

Handle of a help instance.

cbBuffer (ULONG) - input

Initial length of internal buffer.

Initial length of internal buffer where DDF information is to be stored. If this field is 0L, a default value of 1K is defined. The maximum value is 61 440 bytes (60KB).

ulIncrement (ULONG) - input

Amount by which to increment the buffer size, if necessary.

If this field is NULL, a default value of 256 bytes is defined. The maximum value is 60KB.

hddf (HDDF) - returns

Handle to DDF.

A handle to DDF is returned if initialization was successful. Otherwise, the value returned is NULL, indicating that an error has occurred because of insufficient memory or incorrect instance.