From: ahoward <ahoward@...>
Date: 2003-01-29T02:22:10+09:00
Subject: Re: FileTest.size? vs du -b

On Tue, 28 Jan 2003, Curious Person wrote:

> ahoward <ahoward@fsl.noaa.gov> wrote in
> news:Pine.LNX.4.33.0301281641050.8727-100000@eli.fsl.noaa.gov:
>
> <snip>
> >
> > 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.
> <snip>
>
> Well, what I eventually want to do is have a script that fills CDRs up to
> capacity for mkisofs to burn (but not over).  Therefore, I need a way to
> measure size to ensure a good fit on the disc.  I'm not sure which would be
> better; blocks or bytes, though.  Would FileTest.size would be the most
> appropriate method to use?

i'm pretty sure that summing FileTest.size for all files bound for CDR would
be the correct way to go, at least that's how i programmed some backups here
at work.  i don't really know how the iso filesystem works regarding block
size (or if the concept even applies) but, as lyle pointed out, filesystems do
differ.

i think that

  total_size = 0
  files.map {|f| total_size += f.size}

  if (total_size < CDR.size)
    #burn
  end


will work.

-a

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