Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!purdue!bu-cs!madd
From: madd@bu-cs.BU.EDU (Jim Frost)
Newsgroups: comp.unix.questions
Subject: Re: Sparse Files ?  (used often?)
Message-ID: <30792@bu-cs.BU.EDU>
Date: 7 May 89 21:40:23 GMT
References: <19342@adm.BRL.MIL> <30481@bu-cs.BU.EDU> <228@rdahp.UUCP>
Reply-To: madd@bu-it.bu.edu (Jim Frost)
Followup-To: comp.unix.questions
Organization: Software Tool & Die
Lines: 20

In article <228@rdahp.UUCP> scott@rdahp.UUCP (Scott Hammond) writes:
|I'm interested in knowing how much UNIX _application_ software (besides
|news, mailers, or pathalias) uses sparse files.  In particular, given an
|underlying file system implementation which doesn't permit holes, are
|there many of situations where a lot of space is going to be wasted by
|traditional attempts at creating sparse files? 

Not generally, although some common database techniques can create
sparse files (dbm and ndbm packages use techniques which commonly make
sparse files, and dbm/ndbm are often used by applications because
they're already there).  Unless you're dealing with a large database
application, it's unlikely to be a problem, and many databases avoid
sparse files.

In answer to your question, there is not very much application
software which uses sparse files.  Be careful, though -- it only takes
one such application to make your life difficult.

jim frost
madd@bu-it.bu.edu