Sounds like you are doing the right thing. One thing I can think of
is the user needs to login again after the permissions are changed.

Also can the user cat /dev/ttyS0 ?

Cheers,
    
On Fri, Oct 10, 2008 at 11:30:55AM +1100, Erik de Castro Lopo wrote:
> Hi all,
> 
> I'm trying to open a serial port which has the following owner
> ship and group permissions:
> 
>     crw-rw---- 1 root dialout 4, 64 Oct 10 11:05 /dev/ttyS0
> 
> from a process being run by a user with uid and gid of X. However,
> user X is also in the dialout group. 
> 
> However, when the process tried to open /dev/ttyS0 it fails with
> EPERM. I thought X being a member of the group that owns the device
> was sufficent to allow X to open the device.
> 
> Obviously if I add world read/write permissions to the device it
> works.
> 
> Cluebat please?
> 
> Erik
> -- 
> -----------------------------------------------------------------
> Erik de Castro Lopo
> -----------------------------------------------------------------
> "One of Subversions biggest weaknesses is its lack of adequate internal
> tracking for merges." -- William Nagle in "Subversion Version Control"
> _______________________________________________
> coders mailing list
> coders@slug.org.au
> http://lists.slug.org.au/listinfo/coders

-- 
John
http://www.inodes.org/
_______________________________________________
coders mailing list
coders@slug.org.au
http://lists.slug.org.au/listinfo/coders

Reply via email to