Recent change in redirection handling?

Ashok Vadekar avadekar@certicom.com
Fri Jun 4 17:21:00 GMT 2004


On Fri, Jun 04, 2004 at 12:32:46PM -0400, Igor Pechtchanski wrote:
> On Fri, 4 Jun 2004, Ashok Vadekar wrote:
> 
> > I have a bash script that ran cleanly under 1.5.9x, that now exhibits some
> > disturbing behaviour under a recent upgrade.  The gist of the problem is that
> > the execution of
> >         compact /c file.exe >NUL
> > which used to run and produce no output (due to the redirect) now actually
> > puts the output into a file called NUL
> > So, I can deal with the fact that the script needs to either use
> > NUL: (which I did not test) or maybe more appropriately /dev/null (which
> > works), but I now have the NUL files polluting my disk that cannot be removed!
> >
> > Under a real unix shell, I've had occasion to drop down to a bourne shell to
> > delete filenames with wilrdcard characters that a (t)csh would have trouble
> > with, but I have not found a similar was to deal with this.  Using
> >         rm NUL
> > in bash does not work;
> >         rem NUL
> > in a dos box doesn't work, and the windows explorer doesn't either.
> >
> > Any suggestions?
> 
> Known problem.  See <http://cygwin.com/ml/cygwin/2004-05/msg00905.html>
> and <http://cygwin.com/ml/cygwin/2004-06/msg00144.html>.  In particular,
> the thread referenced in the first message should tell you how to remove
> the file.

Thanks for the pointer.

> 
> Incidentally, why do you redirect to NUL rather than to /dev/null?

I usually end up having trouble when I try to use native windows excutables
in bash scripts.  Redmond and I don't seem to see eye-to-eye on parameter passing
etal.  So I end up testing the use of the executables in a DOS box first.  As a
result, I used NUL.  When I put the functionality into the bash script, I just
neglected to use the (unix) cannonical method.  In this particular case, in addition 
to the compact call, I was trying to set up environment variables through the
use of REG, and was having trouble with the quotes and slashes getting handled 
differently by bash and CMD.  Worse yet, the registry manipulation was going
into a sprintf/system() call so that a binary was calling REG, so it was somewhat 
obscured.

> 	Igor
> -- 
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> 
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