How to implement contAcquireNChan.c example from National Instrument with a mex file in matlab 2014b in mac OS

I am trying to build a mex file to acquire data through a NIDAQ USB-6009 device but I am facing troubles when trying to compile the mex file. The NI drivers installed are the 14.0 version which supports 64 bits architecture according to NI (the example compiles and runs in a C Command Line Tool project in Xcode 6.1.1 on my computer)

Here is my code:

#include <math.h>
#include <matrix.h>
#include <mex.h>
#include "NIDAQmxBase.h"
#include <stdio.h>
#include <time.h>

#define DAQmxErrChk(functionCall) { if( DAQmxFailed(error=(functionCall)) ) { goto Error; } }

void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
  // Task parameters
    int32       error = 0;
    TaskHandle  taskHandle = 0;
    char        errBuff[2048]={'\0'};
    int32       i,j;
    time_t      startTime;
    bool32      done=0;

      // Channel parameters
      char        chan[] = "Dev1/ai0, Dev1/ai1";
      float64     min = -10.0;
      float64     max = 10.0;

      // Timing parameters
      char        clockSource[] = "OnboardClock";
      uInt64      samplesPerChan = 1000;
      float64     sampleRate = 5000.0;

      // Data read parameters
      #define     bufferSize (uInt32)1000
      float64     data[bufferSize * 2];
      int32       pointsToRead = bufferSize;
      int32       pointsRead;
      float64     timeout = 10.0;
      int32       totalRead = 0;

      printf("Example will halt automatically.\n");
      DAQmxErrChk (DAQmxBaseCreateTask("",&taskHandle));
      DAQmxErrChk (DAQmxBaseCreateAIVoltageChan(taskHandle,chan,"",DAQmx_Val_Cfg_Default,min,max,DAQmx_Val_Volts,NULL));
      DAQmxErrChk (DAQmxBaseCfgSampClkTiming(taskHandle,clockSource,sampleRate,DAQmx_Val_Rising,DAQmx_Val_ContSamps,samplesPerChan));
      DAQmxErrChk (DAQmxBaseCfgInputBuffer(taskHandle,200000)); //use a 100,000 sample DMA buffer
      DAQmxErrChk (DAQmxBaseStartTask(taskHandle));

      // The loop will quit after 10 seconds

      startTime = time(NULL);
      while( time(NULL)<startTime+10 ) {
          DAQmxErrChk (DAQmxBaseReadAnalogF64(taskHandle,pointsToRead,timeout,DAQmx_Val_GroupByScanNumber,data,bufferSize*2,&pointsRead,NULL));
          totalRead += pointsRead;
          printf("Acquired %ld samples. Total %ld\n",pointsRead,totalRead);
          // Just print out the first 10 points of the last data read
          for (i = 0; i < 10; ++i)
              printf ("data0[%ld] = %f\tdata1[%ld] = %f\n",i,data[2*i],i,data[2*i+1]);

      }
      printf("\nAcquired %ld total samples.\n",totalRead);

Error:
    if( DAQmxFailed(error) )
        DAQmxBaseGetExtendedErrorInfo(errBuff,2048);
    if(taskHandle != 0) {
        DAQmxBaseStopTask (taskHandle);
        DAQmxBaseClearTask (taskHandle);
    }
    if( DAQmxFailed(error) )
    printf ("DAQmxBase Error %ld: %s\n", error, errBuff);

}

And the errors I get while compiling:

Error using mex
Undefined symbols for architecture x86_64:
  "_DAQmxBaseCfgInputBuffer", referenced from:
      _mexFunction in helloWorld.o
  "_DAQmxBaseCfgSampClkTiming", referenced from:
      _mexFunction in helloWorld.o
  "_DAQmxBaseClearTask", referenced from:
      _mexFunction in helloWorld.o
  "_DAQmxBaseCreateAIVoltageChan", referenced from:
      _mexFunction in helloWorld.o
  "_DAQmxBaseCreateTask", referenced from:
      _mexFunction in helloWorld.o
  "_DAQmxBaseGetExtendedErrorInfo", referenced from:
      _mexFunction in helloWorld.o
  "_DAQmxBaseReadAnalogF64", referenced from:
      _mexFunction in helloWorld.o
  "_DAQmxBaseStartTask", referenced from:
      _mexFunction in helloWorld.o
  "_DAQmxBaseStopTask", referenced from:
      _mexFunction in helloWorld.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Answer 1

[Geoff Hayes]

Antoine - how are you building/compiling the above code? The error messages are telling you that you are trying to use functions that haven't been linked with your compiled objects. When you build/compile the function, you will have to link to the libraries that have the _DAQmxBaseCfgInputBuffer, _DAQmxBaseCfgSampClkTiming, etc. functions. I suspect that this linking is taken care of in the Xcode project, so you may want to look more closely at how that has been set up and determine which libraries you will need to include in your

 mex helloWorld.c

build command.

Answer 2

[Antoine]

Sorry, I forgot to add my building line, here it is:

mex -v helloWorld.c  -I"/Applications/National Instruments/NI-DAQmx Base/includes" -L"/Library/Frameworks/nidaqmxbase.framework" -L"/Library/Frameworks/nidaqmxbaselv.framework"

I am referring to this link http://digital.ni.com/public.nsf/allkb/86402BA624A44543862571000001D8BF for the libraries to add.