Readonly Store Changes break Voldemort use on Windows

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The recent changes to the Readonly storage engine break Voldemort on Windows.  
Some unit tests now fail with "Unable to load library 'c': The specified module 
could not be found. ".  Others will hang forever.

The problem resolves around the use of symlinks in the RO Storage Engine, which 
are a recent change.  Depending on whether or not the "C" library is found and 
loaded through JNA, it may hang (see JNA on cygwin section of 
http://mach.debagua.com/archives/2010/0824_001167.html) if loaded or give 
"unsatisfied link exceptions" if the library could not be loaded.

This change causes several new test failures (The entire RO suite, Gossiper, 
Rebalancing, and some AdminBasicTests) to fail, where the tests worked in 
previous versions.  

Some of the tests can be fixed by simply removing the RO store from the 
stores.xml file (when a RO store is not required).  Other tests require code 
changes.

Original issue reported on code.google.com by mramb...@gmail.com on 7 Dec 2010 at 2:08

• Blocking: #340

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Original comment by rsumb...@gmail.com on 12 Jan 2011 at 6:15

• Changed state: Started

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Would it be possible to do something slightly different than what is there now:

- Read/Create the directory called "latest"
- In the latest directory, leave a "version" file that contains what version 
this directory represents (e.g. version-1).
- On a swap, rename "latest" to "version"

I can help work on this change, but am not familiar enough with this store to 
know how it is supposed to work to know whether or not I broke anything.

Original comment by mramb...@gmail.com on 9 Feb 2011 at 10:05

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Lei please re-assign as required.

Original comment by rsumb...@gmail.com on 27 Jul 2011 at 11:50