From mboxrd@z Thu Jan  1 00:00:00 1970
From: Krishna Kumar <krkumar@us.ibm.com>
Subject: Re: Question about netlink
Date: Tue, 08 Jul 2003 13:27:54 -0700
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To: yoshfuji@linux-ipv6.org
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I am still not convinced how it works, though I have been trying to seek the truth for some
time now :-).

These routines 'get' the value of args[0] and then 'set' it to the resultant value. How is
this value set in the first place to the user provided value ? It seems to be initialized
to ZERO in netlink_dump_start(). The only way it seems to use the value is if it gets
called twice from netlink_dump(), the first time cb->args will be set to zero's while the
second time it will have the values set by the first invocation to the same routine. Am I
missing something or is 'args' not intended for user specified arguments ? If so, how
should we access the arguments passed by the user ?

Thanks,

- KK

YOSHIFUJI Hideaki wrote:
> In article <3F0B10E3.9050700@us.ibm.com> (at Tue, 08 Jul 2003 11:43:47 -0700), Krishna Kumar <krkumar@us.ibm.com> says:
> 
> 
>>Some of the netlink routines (eg rtnetlink_dump_ifinfo or inet6_dump_ifaddr) seem to get
>>user arguments from cb->args['n']. However I was not able to figure out where the
>>arguments are being set, can anyone help ?
> 
> 
> Take a look at net/core/rtnelink.c:rtnetlink_dump_ifinfo()
>                net/core/neighbour.c:neigh_dump_{info,table}()
> and seek the truth. :-)
> 
> --yoshfuji
>