Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mstan!chuck
From: chuck@Morgan.COM (Chuck Ocheret)
Newsgroups: comp.unix.internals
Subject: Re: Need efficient way to read file in reverse
Message-ID: <1802@s5.Morgan.COM>
Date: 27 Sep 90 15:38:30 GMT
References: <1990Sep18.152818.1303@phri.nyu.edu>
Organization: Morgan Stanley, & Co., Inc. / New York City, NY
Lines: 15

I recommend that you check to see if your system supports some form of
memory mapping of a file.  On some systems there is the mmap(2) call on
others a version of shmat(2) allows you to do mostly the same thing.
Not all systems provide such a mechanism.  When you map a file in using
either of these you get a pointer to memory which maps directly to a
specified file on the file system (can also be a device).  This gives
you full random access to all bytes in the file.  Read it backwards,
forwards, or however you wish; your file has just become a char *.

~chuck
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