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From Jordan Zimmerman <jor...@jordanzimmerman.com>
Subject Re: behavior of ephemeral nodes
Date Wed, 02 May 2018 17:18:20 GMT
This is less a question of ephemeral node behavior and more a question on how to properly watch
ZNodes. Unfortunately I don't know the C library at all (it looks like that's what you're
using). I can only say that writing code that correctly watches a ZNode is not trivial. Of
course, there may be a bug in the C lib - I know it's not maintained to the same level as
the Java lib.

> On May 2, 2018, at 12:11 PM, Pramod Srinivasan <pramod@juniper.net> wrote:
> 
> any thoughts on this?
> 
> On 5/1/18, 1:43 PM, "Pramod Srinivasan" <pramod@juniper.net> wrote:
> 
>    Hello Everyone,
> 
>    Can someone help me rationalize the behavior I see?
> 
>    1) Process A is watching node /a
>    2) Process B and Process C add ephemeral nodes, say /a/b and /a/c
>    3) Process B and Process C close their session and Process A gets a ZOO_CHILD_EVENT
event when b and c goes away.
>    4) In the context of ZOO_CHILD_EVENT, Process A does a zoo_wget_children for “/a”
and find its empty, but when it tries to delete “/a”, it finds that it is not empty and
zoo_wget_children again returns no children.
> 
>    How can get_children return no children for a znode and a remove of the znode fail
with not empty? It looks like there is a relation with ephemeral nodes and Follower/Leader
behavior, don’t understand this enough to make sense
> 
>    Thanks,
>    Pramod
> 
> 


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