Re: Automounters - more info wanted (was Re: Re: plextor px-708uf: cannot get disk type)

[Lourens Veen <lourens@rainbowdesert.net>]

On Sat 31 January 2004 22:46, Volker Kuhlmann wrote:
> > > >What I meant was those autothingies should keep their hands
> > > > off a disk while a burn process is happening. Dunno whether
> > > > it's possible to detect this, but isn't that the way it
> > > > should be?
> > >
> > > The burner software can open exclusive - see man open.
>
> Yes, even better if the burning software can get access to the
> device in such a way that accesses from other processes result in
> "in use - go away".
>
> > You mean O_EXCL? That doesn't seem to make sense?
>
>        O_EXCL When  used with O_CREAT, if the file already exists
>               it is an error and the open will fail.
>
> My man page doesn't mention anything about E_EXCL when used
> without O_CREAT, but if the behaviour is return success only when
> the device isn't in use (r or w elsewhere) and to prevent
> subsequent processes from opening even read-only, then that looks

As far as I can tell, it says that it won't create or open the file 
if it already exists. I'm just going by the manpage, but it doesn't 
say anything about just opening without O_CREAT (and I reckon the 
device file would exist), let alone that this would prevent other 
programs from opering. If it would work without O_CREAT _and_ these 
automounter opened with O_EXCL, then it might be the solution. But 
I don't see that written down anywhere...

Lourens
-- 
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