watch(8) does not work in jails

[David DEMELIER]

2010/8/16 Roland Smith <rsmith at xs4all.nl>:
> On Mon, Aug 16, 2010 at 11:23:00AM +0200, David DEMELIER wrote:
>> Hi,
>>
>> I enabled `device snp' in my kernel config file and with this I can
>> use the command watch(8) to see any tty device attached. For example :
>>
>> # watch ttyv0
>>
>> Give me the output of the console.
>>
>> But in jails, it's not the same thing, I tried the following :
>>
>> # jexec 1 tcsh
>> # su -
>> People# watch pts/0
>> watch: fatal: cannot open snoop device
>>
>> Is there a limitation of watch(8), or jails ?
>
> Does /dev/pts/0 actually exist in the jail's devfs instance, and are its
> permissions correct?
>

(In jail) :

# ls -l /dev/pts/*
crw--w----  1 markand  tty    0,  94 17 Aug 00:06 /people/dev/pts/0
crw--w----  1 markand  tty    0,  96 17 Aug 00:06 /people/dev/pts/1
crw--w----  1 root     tty    0, 101 21 Jul 00:07 /people/dev/pts/2
crw--w----  1 markand  tty    0, 108 17 Aug 00:06 /people/dev/pts/3
crw--w----  1 markand  tty    0,  99 16 Aug 01:28 /people/dev/pts/4
crw--w----  1 markand  tty    0, 112 17 Aug 00:05 /people/dev/pts/5
crw--w----  1 root     tty    0, 111 17 Aug 00:06 /people/dev/pts/6
crw--w----  1 root     tty    0, 114 16 Aug 23:53 /people/dev/pts/7
crw--w----  1 root     tty    0, 100 17 Aug 00:06 /people/dev/pts/8

I don't understand why pts/0 is given to me since on the host I don't have it :

(On host) :

markand at Orange ~ $ who
markand          pts/6    16 Aug 23:57 (192.168.1.20)
markand          pts/7    16 Aug 23:52 (192.168.1.20)
markand          pts/8    17 Aug 00:06 (192.168.1.20)
markand          pts/9    17 Aug 00:06 (192.168.1.20)

But in the jail pts/0 is affected to a completely different user.

I'm confused.

> Roland
> --
> R.F.Smith                                   http://www.xs4all.nl/~rsmith/
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-- 
Demelier David