Hey everyone, I am trying to do the following using a hybrid of C and Labview: 1.) Create an array in Labview 2.) Pass the array into 2 seperate DLLs at the same time 3a.) One DLL modifies the data and then updates a flag. For example, the array created in 1 in 100,000 units long, this DLL modifies 999 units in one pass and updates the 1000th unit to say that the 999 units have been succesfully written. It would do this 100 times in this example. 3b.) The 2nd DLL checks the flag unit set in 3a, and if the flag is a certain value, the 2nd DLL reads the 999 units modified in 3a and performs operations on them. Note: There is no read/write conflict here, since the only way 3b operates on the memory is if 3a has completed its operations and updated the flag. The problem: Labview creates 3 copies of the same array in memory. Once in step 1, and 1 for each DLL. This is problematic since the 2 DLLs can't communicate with each other anymore in the way that is described above, since the method above requires that the DLLs in 3a and 3b operate on the same memory locations. The question: How can I prevent Labview from creating multiple copies at the Call Library node so that my DLLs can operate on the same chuck of memory that is created in step 1. Thanks, Austin McElroy

LabVIEW

Call Library node and multiple array copies

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Ah, I think I see what is going on now. Initializing an array with a const number is like declaring something in C as a const; it can't be modified unless copied. As long as the array is declared with a variable instead of a constant, array copying won't occur, unless there is a branch, in which case Labview must copy to prevent memory conflicts. This helps out a lot.

Thanks,

Austin McElroy

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LabVIEW

Call Library node and multiple array copies

Re: Call Library node and multiple array copies