Loading VC++ DLL in LabVIEW

Hi,
I am trying to load a VC++ DLL (with two threads) in LabVIEW . Is it possible to maintain the DLL "ALIVE" in memory or it will be loaded in memory only when I am calling the DLL function??
Please provide your comments.
Thanks in Advance.
Regards,
Sathish kumar D

[email protected] wrote:
Hi,
I am trying to load a VC++ DLL (with two threads) in LabVIEW . Is it possible to maintain the DLL "ALIVE" in memory or it will be loaded in memory only when I am calling the DLL function??
Please provide your comments.
Thanks in Advance.
Regards,
Sathish kumar D
Define "alive" here! Normal operation of a DLL is that it provides functions that gets called by the calling application. The DLL is then alive every time one of its functions is called and for the rest it sits dormant and wait.
You mention two threads so seem to spawn two threads from inside the DLL byt one or more function calls. The DLL will stay alive for as long as you let it be. This means as long as one VI is in memory that references one of the DLL functions in a static matter (the DLL path and name defined in the Call Library Node and not passed to it as parameter), LabVIEW will leave that DLL in memory. But once the last VI referencing that DLL is gone, your DLL is forcefully unloaded by LabVIEW no matter what your threads would like to have.
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

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contourcWrapper_test.vi ‏12 KB
libcontour.zip ‏50 KB

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bitte entschuldigen Sie, dass es etwas länger gedauert hat.
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http://digital.ni.com/public.nsf/allkb/0BF52E6FAC0BF9C286256EDB00015230
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Can I Use a Free Compiler with Simulation Interface Toolkit (SIT)?
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CVI RT Missing Export Error when using a DLL from VS2008
http://forums.ni.com/ni/board/message?board.id=180&message.id=41001&requireLogin=False
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Mit freundlichen Grüßen
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Application Engineering,
GERMANY

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