mexPrintf message doesn't show on matlab command window

Question

I started working with mex on matlab to build a c code and I wrote a very simple code (main.c) to begin with :

#include "stdio.h"
#include "stdlib.h"
#include "mex.h"

void main()
{
    mexPrintf("Hello world");
}

when I type mex main.c in a matlab script everything goes well and I have this message : "Building with 'gcc'. MEX completed successfully." but I don't see the message "Hello world", I tried printf() too without success, does anyone know why the message doesn't appear on the matlab window please ?

Thanks in advance for your help.

-J

Answer 1

Your code, as it stands, is not compatible with Matlab. Matlab requires a special function definition for the 'main' function of compiled programs.

In order to run your code, you will need to have something like this:

#include "stdio.h"
#include "stdlib.h"
#include "mex.h"

void mexFunction( int nlhs, mxArray *plhs[],
          int nrhs, const mxArray*prhs[] )
{
    mexPrintf("Hello world\n");
}

Assuming that this is placed in a file entitled, 'helloWorld.c', you can run the following commands at the Matlab prompt:

mex helloWorld.c
helloWorld