[Dxspider-support] [quiet announce] US state filtering

[Dirk Koopman]

On Tue, 15 Oct 2002 08:33:38 +0200
"Arnold (pa4ab)" <Pa4ab at pa4ab.net> wrote:

> 
> On Tue, 15 Oct 2002 02:32:42 +0100
> Dirk Koopman <djk at tobit.co.uk> wrote:
> 
> > On Mon, 14 Oct 2002 13:31:27 +0100
> > Dirk Koopman <djk at tobit.co.uk> wrote:
> > 
> > > In the latest build in CVS I have put in an alpha version of US
> > > State filtering. The build you require is 57.119. 
> > 
> > <snip>
> > 
> > Things have moved on a bit and feedback received has throw up the
> > odd anomaly and enhancement.
> 
> <snip>
> 
> 
> > Here are the instructions from the Changes file:-
> > 1. Download the corrected database from
> >    http://www.dxcluster.org/download/usdbraw.gz to somewhere like
> >    /tmp.
> > 2. update from CVS.
> > 3. Restart (on linux, just stop the node and *don't* restart on
> >    Windows). 4. remove /spider/data/user.v1
> 
> remove /spider/data/usdb.v1 ?

absolutely, yes. Fundamental feature of the way the unix filesystem
works. What I am trying to achieve here is a clean (not updated)
usdb.v1. Create_usdb.pl will update any existing DB. 

[unix tech note no. 23c]

All files in unix systems exist until their inode references counts fall
to 0 *and* they are closed. An example of when this is useful is for
temporary file usage. A common example:-

  FILE *f = fopen("filename", "w+");
  unlink("filename");
  ..
  process_stuff();
  ..
  fclose(f);

What this achieves is a 'private' scatch file which cannot be interfered
with (it cannot be seen, because it no longer exists in a directory). It
exists only as an inode and that only for as long as it remains open.

Dirk G1TLH