Labview(Linux)2021 has an error loading the shared library

[kongmingpeng]

On Linux system (Ubuntu20.04) I loaded a library, I can select the correct function after selecting the library path, but when I click OK, it says that I can't find the loaded library, asking me to make sure that the library path is correct, but the library path is correct, I don't know why this error occurred;

I made a series of attempts:（I will package all images, source code and libraries into attachments）

1. The operation performed to load the library is shown in the image:

2.A strange phenomenon
Trying to repeat step 1, I successfully loaded the compiled library, sometimes with a different name, but the cpp was the same; But after a while, like when I took a nap and my computer wasn't turned off, I went to load the library again and found that the error from step 1 was coming up again, which made me crash😤
3.Remove a library of dds

So I found that libraries compiled from cpp files that don't rely on dds libraries can be loaded no matter how much time has passed; But now I don't know what is the incompatibility of the dds library I compiled that caused the loading failure, because I used the source code to compile the DLL under the window. This makes me feel very frustrated and I don't know how to solve it😢

[wiebe@CARYA]

Wrong bitness?

64 bit dlls need LV 64 bit. 32 bit dlls need LV 32 bit.

[kongmingpeng]

All Environment is 64 bit；

[kongmingpeng · Accepted solution]

Thanks guys，I found the answer to the question：

this link: How does LabVIEW's call library function node search for the path to the shared library? - NI
So I copied all the dependencies to /usr/lib and commented out the shared variables to load the libraries.

At this time, I went to load the library has been stable and will not report errors.But when I loaded the full functionality library, it had another error, but it should be related to other problems, I would be very grateful if anyone knew how to fix it.

[wiebe@CARYA · Accepted solution]

Looks like the API is using mangled function names.

Typical for C++ functions.

The C++ function names contain prototype info, but they're compiler specific.

There (several) compiler options to prevent the export of mangled file names, but google will probably serve you better than me.

[kongmingpeng]

Thanks for your reply.

I'll look it up.