[sane-devel] configure check for locking fails as non-root ...

Gerhard Jaeger gerhard@gjaeger.de
Mon, 11 Apr 2005 09:12:29 +0200


On Friday 08 April 2005 17:42, Julien BLACHE wrote:
> Gerhard Jaeger <gerhard@gjaeger.de> wrote:
> 
> Hi,
> 
> > sorry for the late response. 
> > These are the problems, that I've expected, when introducing this
> > feature. But I have no idea how to solve it! 
> 
> Well, disabling the locking if your check fails, instead of aborting
> the configure script would be a good start :) 

Hmmm, not my favourite way, but probably a better one ;)

> Correcting the error message would be good too, this one is misleading ;)
Oh yes, of course, the current one is more than ugly.

I'll fix both issues today.

> > Have you any idea how to solve such an issue?
> > I'd like to have this feature and therefore I also added the
> > possibility to change this default uucp-group:
> > --with-group=your_group
> >
> > Any other comments?
> 
> The programs usually locking the serial port are run setuid root or
> uucp or something, so they can write the lock file in /var/lock.
> 
> This is not applicable to SANE, because SANE's only the middleware
> (and thus, cannot do setuid()).
> 
> Quite honestly, I have no (portable) idea. Maybe something based on
> shared memory could work. If something comes to my mind, I'll share my
> thoughts about that :)

Okay, I will also spend some time in investigation on the shared memory
trail...

Thanks
Gerhard