unix file structure (or lack of same)

[Thomson]

I'm curious about something:

I understand that, on unix, the file system is designed so that a file always
looks like a sequence of bytes, with no record structure at all.

Is this correct?

If so, how does one implement an efficient database manager on unix in
a standard, portable, way?  To be efficient, a database manager needs to
have random access into files on a record-oriented basis.  It seems to me
that fseek() wouldn't do the job.  (Am I wrong here?)  If unix doesn'`t
provide a record-oriented view of files, then any database implementation 
would have to go below unix, and access the mass storage devices directly.

Is this right?

I know there are database managers for unix, so there must be ways to
do it....

I'm just curious about this, not planning to write
a huge efficient database manager for unix or anything...


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