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My Rules

This small collection of documents should describe disk structures that are widely used in IBM PC and clones. The audience is programmers who wish to implement one or more file systems. I will not make any attempt to describe physical storage interfaces or any programs that work with storage devices.

Before we start, I would like to make some things clear. First of all, in no way should these documents be considered official sources. I, the author, have nothing to do with those who make standards. Therefore, all this information comes without any warrantee. Secondly, the shortmindliness of operating system makers made hard disk structures unnecessarily complex and limited. That is why I recommend applying the good old rule: accept any kind of input, but be conservative in what you output. I will try to be as clear as possible in describing what is commonly acceptable and what you can expect to be on your hard disk. But please understand that no sane programmer can predict what will the standards be a couple of years later. That is why check dates of the documents before relying on them.

My descriptions might seem biased. One might ask why I gave clear preference to describing Microsoft operating system structures. One of the reasons is my involvement in operating system programming and the need to be compatible with current software. Another reason is the stream of questions in  comp.lang.asm.x86  and  alt.lang.asm  newsgroups, all related to FAT file system.

Finally, do not hesitate to contact me in case you have any suggestions related to these documents. I am especially interested if you find any errors or unclear statements. Or you just might tell me how much you love me.

Author:  Alex Verstak  3/10/1998