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RE: Order "begin" probes are run


On Wednesday, November 29, 2006 1:57 PM, Stone, Joshua I wrote:
> On Wednesday, November 29, 2006 1:23 PM, Frank Ch. Eigler wrote:
>> Mike Mason <mmlnx@us.ibm.com> writes:
>>> Seems reasonable to expect tapset "begin" probes to always run
>>> before a script's "begin" probe. [...]
>> 
>> One might also imagine cases where it could work the other way.
>> 
>> We could solve this by parametrizing: adding a sequence parameter to
>> "probe begin(N)" (and "end(M)"), and sorting them.  Easy to
>> implement. 
> 
> This is a nice idea -- if you make the default priority zero for those
> who don't specify it, then things can "just work".  Users can write an
> unparameterized 'begin' as usual, and the tapset writer can initialize
> in a 'begin(-1)' -- or 'begin(-2^63)' if paranoia kicks in...

This is now implemented -- you can give a numeric parameter to begin/end
probes, and they will execute in increasing order.  The sequence number
if left out is effectively zero.

We should adopt a convention for tapset writers to use these fields.  My
suggestion: when it doesn't matter, just use begin/end without a
parameter; to run early, use less than -1000; and to run late use
greater than 1000.  This way script writers still have +/- 1000 to play
with locally.


Josh


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