Working With Files
AutoLISP can only work with ASCII files. This means you can really only work with normal letters and symbols and numbers (i.e. what you can make with a keyboard
You can actually work with some of the other characters, but it is not easy or recommended
As a result, AutoLISP will only work with files in sequential mode, meaning that you have to start reading at the beginning of the file, and read it from there towards the end. However, you do not have to read it to the end.