> Is there a simple compile flag or library include that will avoid this > problem so that I can read and write sequential binary files on the > 64-bit machine that are just the same as on 32-bit machines with g77?? short answer is no. i see that you have two options: #1. Make a custom version of the g77 compiler that uses fixed 32 bit record markers. #2. Write a filter program that converts from 64-32 bit record markers. HTH, bud davis