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After running:

env  ; #from with in terminal

I see the following output:


What is this environment variable used for? Not really finding anything about what its for and why it is set by default.

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Why are you asking? – bneely Mar 6 '12 at 17:41
Because I have read this – MrDaniel Mar 6 '12 at 17:56
Is there a specific problem you're trying to solve, or are you just curious? – bneely Mar 6 '12 at 17:58
Yes what thats variable is for, I think the answer solves that... – MrDaniel Mar 6 '12 at 18:00
up vote 7 down vote accepted

PubSub is the backend for how Safari and Mail handle RSS feeds. There are command line utilities too. From the pubsub man page:

pubsub -- Utility for managing RSS/Atom subscriptions via the PubSub framework

This variable is just part of that process.

The ability to read RSS feeds in Safari is going away in Mountain Lion, but I don't know if the entire RSS infrastructure is going away too.

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