[redhead]

You want the code for it? or what??

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char** argv)
{
  int ret=0;
  if(argv != 3)
  {
     printf("Usage %s [directory] [program]\n", argv[0]);
     return -1;
  }
  if(!chdir(argv[1]))
     if(!(ret=system(argv[2])))
        return 0;
     else
     {
        printf("Failure executing %s\n", argv[2]);
        return ret;
     }
  else
  {
     printf("Failure changing to %s\n", argv[1]); 
     return -1;
  } 
}

Or do yu want a more complex code, where you dup(), fork(), write(), read() and waitpid() for the program execution. So you capture everything your external execution does.

Can't .NET compile to something like a [selbstendiger/Selvstændig] app, sorry can't remember the english name..
Else get Cygwin