C / C++ / MFC

HKEY hKey;
TCHAR szDefaultMailClientPath[MAX_PATH] = {0};
DWORD dwSize = MAX_PATH;
if (RegOpenKeyEx(HKEY_CLASSES_ROOT, _T("mailto\\shell\\open\\command"), 0, KEY_READ, &hKey) == ERROR_SUCCESS &&
	RegQueryValueEx(hKey, _T(""), 0, NULL, (BYTE*)&szDefaultMailClientPath, &dwSize) == ERROR_SUCCESS)
{
	CString sPathWithCL(szDefaultMailClientPath);
	CString sPath = sPathWithCL.Mid(sPathWithCL.Find('"') + 1,sPathWithCL.ReverseFind('"') - sPathWithCL.Find('"') - 1);
	CString sEnvString = sPath.Mid(sPath.Find('%'),sPath.ReverseFind('%') - sPath.Find('%') + 1);
	if (sEnvString.GetLength())
	{
		TCHAR szEnvStringResolution[MAX_PATH] = {0};
		ExpandEnvironmentStrings(sEnvString,szEnvStringResolution,MAX_PATH);
		sPath.Replace(sEnvString,szEnvStringResolution);
	}
	MessageBox(sPath);
}

//szDefaultMailClientPath =>"%ProgramFiles%\Outlook Express\msimn.exe" /eml:%1
//sPath => %ProgramFiles%\Outlook Express\msimn.exe
//sEnvString => %ProgramFiles%
if (sEnvString.GetLength()) //this checks whether any env. string is found (may the full path was stored in registry! i.e. c:\\Program Files)
{		
  TCHAR szEnvStringResolution[MAX_PATH] = {0};//this is what %ProgramFiles% will map to (normally c:\\Program Files) 		
  ExpandEnvironmentStrings(sEnvString,szEnvStringResolution,MAX_PATH);//this line asks the OS to resolve the actual meaning of %ProgramFiles%		
  sPath.Replace(sEnvString,szEnvStringResolution);//we change %ProgramFiles% to c:\\Program Files	
}	
MessageBox(sPath);//if no env string was found this (see if statement) this is the full path else we changed it to full path

// Open the file in text mode
FILE* fInput = fopen("red64.txt", "rt");<DIV>

if ( !fInput )
   return;<DIV>

// Create buffers to hold readed data and temporary data
char buffer[20] = { NULL };
char number[8] = { NULL };
double red64[64];<DIV>

// Access the file
int nDoublePos = 0;<DIV>

while ( !feof(fInput) )
{
      // Read a line from the file
      fgets( &buffer[0], 19, fInput );<DIV>

      // Step through the line, copying digits and decimal points
      int nPosition = 0;
      int nLinePos = 0;<DIV>
      while ( buffer[nLinePos] != '\n' )
      {
           if ( isdigit( buffer[nLinePos] ) || buffer[nLinePos] == '.' )
           {
                  // Copy it to the buffer
                  number[nPosition++] = buffer[nLinePos];
           }<DIV>
            // Move to next character on the line
           nLinePos++;
       }<DIV>

       // Now we have readed one double value into a character string, so convert
       if ( number[0] != NULL )
            red64[nDoublePos++] = atof( &number[0] );<DIV>

       // Clear the buffers & move to the next line
       memset( &buffer[0], 0, sizeof(buffer) );
       memset( &number[0], 0, sizeof(number) );
       
}