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Date: Tue, 05 Jul 2011 08:01:23 -0700 (PDT)
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Subject: Re: [PATCH v2 net-next af-packet 1/2] Enhance af-packet to provide
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From: chetan loke <loke.chetan@gmail.com>
Date: Tue, 5 Jul 2011 10:53:26 -0400

>> Next, having this overlay thing is entirely pointless.  Just refer to
> 
> It is useful.
> Also, future versions of the block-descriptor can append a new field.
> When that happens,
> none of the code needs to worry about the version etc for the unchanged fields.

That issue only exists because you haven't defined a common header
struct that the current, and all future, block descriptor variants can
include at the start of their definitions.

I still contend that all of these abstractions are too much and
unnecessary.

Use real data structures, not opaque "offset+size" poking into the
descriptors.