From: ahoward <ahoward@...>
Date: 2003-01-29T01:42:03+09:00
Subject: Re: FileTest.size? vs du -b

On Tue, 28 Jan 2003, Curious Person wrote:

<snip>
> Er... something doesn't add up.  BTW, when I verify the filesizes with ls -
> al, it matches what FileTest.size returns.  Does anyone know what's going
> on here?  Is du inaccurate?
<snip>

du -> 'disk usage'

  this is the amount of disk used by the file, it will always be a multiple of
  the block size whether or not you ask du to show this in bytes or whatever

FileTest.size reports the actual size of the file as reported by stat.  this
is the actual length of the file.

so accurate depends on you viewpoint : if you are concerned about the total
size of files on disk the du is more accurate, if you simply want to know the
size of a file to, for example, read it into a malloc'd array then stat
(FileTest.size) is the way to go.  all you can really count on is that

  du file >= stat.size file

-a

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