>>>Since the checksum is just digits, which are the same in all codepages, you couldn't have added any content which would be in a codepage different from the rest of the file.
>>
>>Not necessarily true.
>>
>>Only true if
>>(1) txt file with UTF8 BOM, or
>>(2) txt file without BOM
>
>Nope
>
>The chars added will follow the BOM / not BOM.
>If you open up a dbf, add something and write, it will follow the rules of the dbf. It might corrupt the file - but it will be interpreted as a part of a dbf.

Sure, the chars added will be after the BOM.

And still, if you add chars ( = bytes in this case) below 0x80 and the text file has a UTF16 BOM, you are in trouble - guaranteed