hey all, allegro cc!
ive just joined the forums and must comment on this, when argv[0] is not the absolute path of my allegro game (in my case "F:\Allegro_Stuff\RTS2\bin\sws.bin") my datafile does not load correctly. I am starting my game module with a separate app with a menu and options and the like and its just starting the game with no user selected options just yet to see if it works. The calling app is written in C#, the game that its starting, and will eventually send the user selected options data to is written in C++. The calling app is using system("start bin\\sws.bin"); to start it.

So to the heart of my problem here; when the game is launched through the calling app argv[0] is shown to be bin\sws.bin and cause my datafile to not load. When I start the game through my IDE's execute command argv[0] is shown to be F:\Allegro_Stuff\RTS2\bin\sws.bin the datafile works fine. Any suggestions or is this just a limitation of allegro 4.5?

What we've done to counter this issue is to use get_executable_name() to change the current directory where appropriate (ie. before loading data within the application's folder).

The code im using to load the datafile is:

inline void LoadGUI()
{
       gui_data = load_datafile("data/GUI.dat");
       if(gui_data == NULL)
       {
                   allegro_message("Could Not Load GUI.dat");
                   exit(EXIT_FAILURE);
       }
       _button = (BITMAP*)gui_data[0].dat;
       _buttonhighlight = (BITMAP*)gui_data[1].dat;
       gui_menu.CreateItem();
       return;
}

i do not understand the tehcnique that you linked to. Some explanation please?

the code the calling app is using is:

[DllImport("msvcrt.dll")]
    public static extern int system(String cmd);

//tonn of other stuff

system("start bin\\sws.bin");

thx for the speedy response Matthew, I copied and pasted the code you just posted however now the function is not even reporting that the data file is NULL, instead its just outright crashing 0.o

K Matthew, thanks anyway for your help.