Include external libraries in Mex files

I am just playing around with mex files and wish to call an external library in a mex file. I have this code and some more after it. The linking fails even though I include everything in the -I -L and -i options.

#include "gdcmImageReader.h"
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
char *filename;
filename = mxArrayToString(prhs[0]);
gdcm::ImageReader reader;
reader.SetFileName( filename );

then when I compile I get something like this

error LNK2019: unresolved external symbol "public: void __cdecl gdcm::Reader::SetFileName(char const *)" (?SetFileName@Reader@gdcm@@QEAAXPEBD@Z) referenced in function mexFunction

Are you allowed to call external libraries?

[James Tursa]

You need to show us the exact commands you are using to mex the code. What you are currently doing is not linking in the necessary libraries.

[Muser10101010]

Hi, this is the code so far

#include "gdcmImageReader.h"
#include <iostream>
#include <stdio.h>
#include "mex.h"

using namespace gdcm;

void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
  char *filename;
  FILE * pFile;

      if( nrhs != 1 || !mxIsChar(prhs[0]) ) {
          mexErrMsgTxt("Need filename character string input.");
      }
      filename = mxArrayToString(prhs[0]);
      pFile= fopen(filename, "rb");
      mxFree(filename);
      if( pFile == NULL ) {
          mexErrMsgTxt("File did not open.");
      } 
        
    gdcm::ImageReader reader;
    reader.SetFileName( filename );
    if( !reader.Read() ) {
          char str[80];
          strcpy(str, "could not read the dicom file: ");
          strcat(str, filename);     
          mexErrMsgTxt(str);        
    }
  }

I then compile with this (I have the .lib files in pwd/lib and include files in pwf/include)

mex -v -I.\include -L.\lib -lgdcmCommon -lgdcmDICT -lgdcmDSED -lgdcmIOD -lgdcmMEXD -lgdcmMSFF -lgdcmcharls -lgdcmexpat -lgdcmgetopt -lgdcmjpeg12 -lgdcmjpeg16 -lgdcmjpeg8 -lgdcmopenjpeg -lgdcmzlib -lsocketxx  testreader.cpp