Re: File list on Windows and Debian

[M E Leypold <development-2006-8ecbb5cc8aREMOVETHIS@ANDTHATm-e-leypold.de>]

Anders Wirzenius <anders@no.email.thanks.invalid> writes:

> "Ludovic Brenta" <ludovic@ludovic-brenta.org> writes:
> 
> > Anders Wirzenius writes :
> > > I am trying to process files in a directory. They have to be processed
> > > in alphabetical order. With following code I get a nice sorted list on
> > > Windows XP but not sorted at all on Linux Debian. Have I missed
> > > something that switches the sorting on on Debian (Sarge)?
> > 
> > I tried your program at home, and had to tweak it a little bit for it
> > to compile. Then I also ghot unsorted directory entries, like I did
> > with another program I wrote.
> > 
> > I think this is by design on GNU/Linux systems. They don't impose the
> > overhead of sorting potentially large numbers of directory entries
> > unless you really need to sort them.

That is correct. I suppose that the Gnat directory functions just
interface to readdir(3) and with readdir() the order of entries is
dependend on the underlying filesystem. In ext2fs this is AFAIS the
order in which they are written (a directory is just a file with
dirent records, actually), with xfs (which uses btrees internally)
entries get retrieved mostly sorted but AFAIR "." and ".." are not the
first two and so on. I'd expect different results for reiser fs also.

Regards -- Markus