A function to retrieve the directory of a program

Introduction

I've needed to get the directory a program was running several times. I've used it to determine where configuration files could be found. I've used it for determining where images should be stored/loaded. I've also had to write it from scratch several times :( . I'm submitting it here so hopefully someone else doesn't have to figure it out themselves.

I've found that using _getcwd isn't accurate whenever the user is allowed to use the file dialogs to open or save files. If they move to a different directory in the file dialogs, the current working directory is changed as well

CString GetProgramDir()
{
    CString RtnVal;
    char    FileName[MAX_PATH];
    GetModuleFileName(AfxGetInstanceHandle(), FileName, MAX_PATH);
    RtnVal = FileName;
    RtnVal = RtnVal.Left(RtnVal.ReverseFind('\\'));
    return RtnVal;
}

It's not much, but I've found it helpful and hope that someone else will as well.