Help!!!!! with Input from file

I need a way to get info from THE END an autocad .dwg file
this is not as simple as it sounds seeing as how the
program keeps telling me that the EOF is after the FIRST LINE so now you see my predicament im having no problem writing to the end of the file (i write a string to the end of the file so that i can track it) but i cant read that string at the end of the file because of the eof problem...
Please help!!!!

I might be all wrong here but try writing your own functoin that test for eof by getting the file length and then for every line just subtracting the len() value + 1 of the line from the total file size and then when it hits 0 you know its eof. It might work, but I don't know what a .dwg file is.

If you open your file in Input, the EOF will not be correct for almost all non-text files. Therefor open in Random or Binary.