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Fonctions Windows API
>I am trying trying to call a DLL function. The VB code that works properly is as Follows:
>
>//////////////////////////
>Declare Function FPInitialize% Lib "ETFAXD32.DLL" (lpdFaxHandle&)
>
>Private Sub Command1_Click()
>
> wstatus = FPInitialize(dFaxHandle)
>
>End Sub
>/////////////////////////
>
>In this code, the value of dFaxHandle is properly assigned a Long Integer value, and wstatus is assigned 0, indicating success.
>
>I'm trying to do the samething in VFP 5.0. Here is the code for VFP:
>
>DECLARE INTEGER FPInitialize IN ETFAXD32 AS FpInitialize ;
> Long @nFpHandle
>
>nStatus = FpInitialize(@nFaxHandle)
>
>As near as I can tell, this should return the samething, but a Long integer gets assigned to nFaxHandle(as I would expect) and a large integer gets assigned to wStatus, indicating failure.
>
>This seems simple enough, what am I missing here?
>
>Ed
You need to initialize the nFaxHandle before the call to FpInitialize. VFP doesn't initialize variables passed as params to a DLL function.
So, include a
nFaxHandle = 0
before nStatus = ...
Vlad
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