Modern 2.6 kernels - Notification for changing hostname from proc/sys/kernel/hostname ?

Modern 2.6 kernels - Notification for changing hostname from proc/sys/kernel/hostname ?

[Shawn Starr]

Hello, 

I was looking at utsname_sysctl.c (if this is the right place) and noticed 
there doesn't seem to be any notification via the connector bus to tell 
userspace the hostname has changed? Is this correct?

if so, would not not make sense to add such event triggers so that things like 
KDE would not have to poll to determine if the hostname changes and instead 
had D-BUS tell userspace the hostname changed?

Perhaps this could be applied to other values (where applicable) 
in /proc/sys/kernel?

Or is this all going to go into sysfs eventually (where some of this really 
might belong)

Thoughts?

Thanks, 
Shawn.

Re: Modern 2.6 kernels - Notification for changing hostname from proc/sys/kernel/hostname ?

[Alexey Dobriyan]

On Mon, May 19, 2008 at 01:16:12PM -0400, Shawn Starr wrote:
> I was looking at utsname_sysctl.c (if this is the right place) and noticed 
> there doesn't seem to be any notification via the connector bus to tell 
> userspace the hostname has changed? Is this correct?

Yes. No notifications.

> if so, would not not make sense to add such event triggers so that things like 
> KDE would not have to poll to determine if the hostname changes and instead 
> had D-BUS tell userspace the hostname changed?

Why does it want to know if and when hostname changes?

> Perhaps this could be applied to other values (where applicable) 
> in /proc/sys/kernel?

Probably, what other stuff desktop crowd wants?

> Or is this all going to go into sysfs eventually (where some of this really 
> might belong)

Hopefully, not. There is already uname(2), sysctls -- proc and binary,

Re: Modern 2.6 kernels - Notification for changing hostname from proc/sys/kernel/hostname ?

[Shawn Starr]

On Monday 19 May 2008 04:45:35 pm Alexey Dobriyan wrote:
> On Mon, May 19, 2008 at 01:16:12PM -0400, Shawn Starr wrote:
> > I was looking at utsname_sysctl.c (if this is the right place) and
> > noticed there doesn't seem to be any notification via the connector bus
> > to tell userspace the hostname has changed? Is this correct?
>
> Yes. No notifications.
>
> > if so, would not not make sense to add such event triggers so that things
> > like KDE would not have to poll to determine if the hostname changes and
> > instead had D-BUS tell userspace the hostname changed?
>
> Why does it want to know if and when hostname changes?
>
Well, It's for keeping track of the X session, if the hostname changes things 
go bad.

> > Perhaps this could be applied to other values (where applicable)
> > in /proc/sys/kernel?
>
> Probably, what other stuff desktop crowd wants?

No idea on the other values, but maybe others can jump in on this discussion?

>
> > Or is this all going to go into sysfs eventually (where some of this
> > really might belong)
>
> Hopefully, not. There is already uname(2), sysctls -- proc and binary,

Hopefully this can all be cleaned up, we really should have one unified place 
for kernel tweaking/settings either /proc or /sys.

Re: Modern 2.6 kernels - Notification for changing hostname from proc/sys/kernel/hostname ?

[Jan Engelhardt]

On Monday 2008-05-19 22:05, Shawn Starr wrote:
>>
>> Why does it want to know if and when hostname changes?
>>
>Well, It's for keeping track of the X session, if the hostname changes things 
>go bad.

Then these should be resolved. Sometimes, even setting just the time
with ntpdate makes X go blank for a few seconds, or even exit.