A different way to do "dirty reads." By this I mean avoiding any locking for reading records in threaded code. Possibly useful for rarely updated data...
type struct __dirtyread_t {
   double currency_rate;
   int read_count;
} dirty_read_t;

How would this be used is as follows:

dirty_read_t yenToDollars; //currency conversion
//read_count is initialized somewhere else...
//.. declare necessary variables...

do {
   my_count = yenToDollars.read_count;
   my_conv_rate = yenToDollars. currency_rate;
   // calculate... 

} while ( my_count != yenToDollars.read_count);
// The
Something like this could work assuming the currency rate changes only once or twice a day.