I asked a similar question a few days ago here (but it is far down, so you
probably didnt see it). I asked how to convert a String* to a char[]. This
is how I ended up doing it:

char  char_array[32+1] ;
String* string_thing = new String("Hello") ;

for ( int c=0 ; c < length ; c++)
{
  char_array[c] = char(string_thing->chars[c]) ;
}

char_array[length] = '\0' ;

After this code is executed:  char_array contains null-terminated "Hello".

So, in your case the 'string_thing' is your filename argument and char_array
is similar to char* (it is easy to change to using char* instead, as
char_array is almost a char*....hehe).

Hope this helps... :)

[==Peteroid==]

I think this should do it.. (first one is String * to stl string, second is
the opposite. You can extract the raw char pointer from an STL string using
c_str().

std::string STLStringFromDotNetString( System::String *str)
{
   //get a pointer to an array of ANSI chars
   char *chars = (char*) Marshal::StringToHGlobalAnsi(str).ToPointer();
   //assign the array to an STL string
   std::string stl = chars;
   //free the memory used by the array
   //since the array is not managed, it will not be claimed by the garbage
collector
   Marshal::FreeHGlobal(chars);
   return stl;
}

System::String * DotNetStringFromSTLString( const std::string &str)
{
   return Marshal::PtrToStringAnsi((int*) str.c_str());
}

Steve