acess predefined buffer

[kevinhy]

I have a dll function that defines a buffer and a second dll function that writes to the buffer. However the buffer is not directly wired into the second function; the function "gets to know" the buffer by a structure handle that goes through each and every functions in this dll. I need to save the data in the buffer after the second dll write to it and I haven't found a way to do so. I have tried to create a local variable of the buffer and extract data out of the local variable. When I check the obtained data, no data has been written to the locate variable. it seems that when I create the local variable labview made a second copy of the buffer and no data has been written to the second copy. If I am to be correct, the question is how to access the real buffer that contains the real data, So far I have not got a clue how to do that.


kevin

[rolfk]

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@kevinhy wrote:
I have a dll function that defines a buffer and a second dll function that writes to the buffer. However the buffer is not directly wired into the second function; the function "gets to know" the buffer by a structure handle that goes through each and every functions in this dll. I need to save the data in the buffer after the second dll write to it and I haven't found a way to do so. I have tried to create a local variable of the buffer and extract data out of the local variable. When I check the obtained data, no data has been written to the locate variable. it seems that when I create the local variable labview made a second copy of the buffer and no data has been written to the second copy. If I am to be correct, the question is how to access the real buffer that contains the real data, So far I have not got a clue how to do that.


kevin

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LabVIEW can't easily access external memory. While there might be some way to do it, if I knew the exact details for the DLL, it would be going to be extremely complicated and difficult to explain. The most simple way is to actually add a function to the DLL which gets the "handle" as parameter and as second parameter a byte array in which that function copies the data you are interested in from that handle.

Rolf Kalbermatter