icon cache scriplet guideline update

[Rex Dieter]

Bill Nottingham wrote:
> Matthias Clasen (mclasen at redhat.com) said: 
>>> if we have to run it it in the rpm transaction.  it should be run only once 
>>> per rpm transaction not once per rpm. 
>> That's one thing to consider for the "revive rpm development" effort.
> 
> The logical place to do things like this would be in a yum plugin.
> However, that's going to run into the 'don't want to use yum' problem,

rpm plugins?  (:

> so you start having to tie hooks into rpm itself, which leads you to
> macro-ization of everything, %define __post_transaction_hook, a mechanism
> to pass arbitrary transaction data from a commandline program to another
> commandline helper... fun.

fun indeed.  From what I've seen so far, something along those lines 
seems to be the best solution to this general type of problem 
(similar/same scriptlets being repeatedly run within the same rpm/yum 
job/transaction).