New "info auxv" command and $auxv variable?

[Andrew Cagney <ac131313@redhat.com>]

Hello,

In implementing a mechanism to query values from the the target's AUXV 
(/proc/$$/auxv) I decided I might as well add a generic command:

	(gdb) info auxv
	Entry point 0x1234
	...
	(gdb)

that listed the contents of the processes auxv table.

But why stop there?  What about a builtin $auxv variable, a struct, vis:

	(gdb) print $auxv
	$1 = { entry = 0x1234, ... }

Oh, and I guess:

	(gdb) interpreter mi --info-auxv
	^ok,result={entry="0x1234",...}

Thoughts?
Andrew

PS: Can any one point me at an official GNU/Linux or, I guess *BSD, 
distro that supports /proc/$$/auxv?  So far I've only got Solaris :-/

PPS: The second one is actually tricky.  It requires a type bound to the 
lifetime of the inferior - it is only in querying the inferior that the 
fields can be determined.  An alternative would be to always create the 
type and then shove it into a type system bcache - ensuring that only 
one struct of that form exists.