Hi, I’m trying out Mathematica to connect our shared library to Mathematika but I have problems during running functions in the shared Library. So I started with a test shared library. Some parts work fine so far. At first what worked:

1.  AppendTo[$LibraryPath,  ToFileName["/slowfs/lithop4-nb-2/egger/Mathematica/Tests"]];

2.  LibraryLoad["libtestlib"]

3.  INTTEST2 =  LibraryFunctionLoad["libtestlib", "Inttest2", {Integer, Integer}, Integer]

That worked so far. But running

INTTEST2[10, 101]

returned an error message:

LibraryFunction::rterr: An error with return code -1429266942 was encountered evaluating the function Inttest2. >>

I used Red Hat Enterprise Linux Client release 5.7 (Tikanga) and gcc version 4.1.2 20080704 (Red Hat 4.1.2-51). Building the test shared library was done by

gcc -c -g -fPIC testlib.cpp -I.

gcc -shared -o libtestlib.so testlib.o

The console output from my shared library was:

Inttest2 parameter 1 is -1429266944 and parameter 2 is 2

Inttest parameter is -1429249280

I added two attachments testlibheader.txt that contains the header file testlib.h and testlibsource.txt in unix text format.

The interesting lines of the header are:

void Inttest1(int iTest);

int Inttest2(int iTest, int iTest2);

and of the cpp file are:

void Inttest1(int iTest) { std::cerr << "Inttest parameter is " << iTest << std::endl; }

long Inttest2(long iTest, long iTest2) { std::cerr << "Inttest2 new parameter 1 is " << iTest << " and parameter 2 is " << iTest2 << std::endl; long iSum = iTest + iTest2; return iSum; }

I hope you can help me with that problem. Kind regards, Roland

Hello Szabolcs,

thank you, too. I found a tutorial link above.

http://reference.wolfram.com/language/LibraryLink/tutorial/Overview.html

If you know another interesting link for me please send it. Best regards, Roland

From looking at the source you posted, you haven't included the WolframLibrary.h header or the DLLEXPORT type; have you gone through the LibraryLink "User Guide"?

In general, to call a function like this, you'll need some sort of interface function like:

DLLEXPORT int demo1_I_I( WolframLibraryData libData, mint Argc, MArgument *Args, MArgument Res) {
    mint I0;
    mint I1;
    I0 = MArgument_getInteger(Args[0]);
    I1 = I0 + 1;
    MArgument_setInteger(Res, I1);
    return LIBRARY_NO_ERROR;
}

(this gets an integer from M, add 1 to it, and then returns it to M)

Hello,

has anybody any experience with LibraryFunctionLoad?

Kind regards,

Roland