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From: Topher <javert42@cs.byu.edu>
To: linux-c-programming@vger.kernel.org
Subject: mmap questions
Date: Mon, 17 Dec 2007 22:51:43 -0700	[thread overview]
Message-ID: <47675FEF.2010903@cs.byu.edu> (raw)

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I've read through the man pages on mmap, munmap, and msync, and I still
am not sure that I'm using the correct flags.  Actually, I'm not even
completely sure that mmap is the way to go.

I'm creating a queue-like data structure that uses a fixed amount of
heap space.  When it fills up, it must dump itself to a file, and then
it can consider itself "cleared", and continue adding elements.  If a
remove() call is made on the structure, and it's currently empty but has
previously dumped to disk, it loads the data from disk, and then
continues.  Also, this is only a single-threaded application.

I thought that I should use the MAP_PRIVATE flag when I map the file,
then just munmap() then call close(fd) when I dump it, but that's not
working.  I'm just getting empty files.

Is mmap even the way to go, or should I just be using write() and read()?


-- 
Topher Fischer
GnuPG Fingerprint: 3597 1B8D C7A5 C5AF 2E19  EFF5 2FC3 BE99 D123 6674
javert42@cs.byu.edu | http://www.thetopher.com


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             reply	other threads:[~2007-12-18  5:51 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-18  5:51 Topher [this message]
2007-12-18 17:17 ` mmap questions Glynn Clements

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