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https://issues.apache.org/jira/browse/HDFS-573?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14081555#comment-14081555
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Stephen Bovy commented on HDFS-573:
-----------------------------------

Thanks,

I am probably exposing  my ignorance, so please forgive me.   Are you saying 
that using JNI automatically implies and requires thread support, and that 
every JNI call is running on a thread?   

My hdfs client does  not use threads, so each hdfs call is  synchronous, and 
each jni call is also synchronous, and within the
context the code accessing the hash table should also be synchronous.  Please 
correct me gently if I am wrong :) 


> Porting libhdfs to Windows
> --------------------------
>
>                 Key: HDFS-573
>                 URL: https://issues.apache.org/jira/browse/HDFS-573
>             Project: Hadoop HDFS
>          Issue Type: Improvement
>          Components: libhdfs
>         Environment: Windows, Visual Studio 2008
>            Reporter: Ziliang Guo
>            Assignee: Chris Nauroth
>         Attachments: HDFS-573.1.patch
>
>   Original Estimate: 336h
>  Remaining Estimate: 336h
>
> The current C code in libhdfs is written using C99 conventions and also uses 
> a few POSIX specific functions such as hcreate, hsearch, and pthread mutex 
> locks.  To compile it using Visual Studio would require a conversion of the 
> code in hdfsJniHelper.c and hdfs.c to C89 and replacement/reimplementation of 
> the POSIX functions.  The code also uses the stdint.h header, which is not 
> part of the original C89, but there exists what appears to be a BSD licensed 
> reimplementation written to be compatible with MSVC floating around.  I have 
> already done the other necessary conversions, as well as created a simplistic 
> hash bucket for use with hcreate and hsearch and successfully built a DLL of 
> libhdfs.  Further testing is needed to see if it is usable by other programs 
> to actually access hdfs, which will likely happen in the next few weeks as 
> the Condor Project continues with its file transfer work.
> In the process, I've removed a few what I believe are extraneous consts and 
> also fixed an incorrect array initialization where someone was attempting to 
> initialize with something like this: JavaVMOption options[noArgs]; where 
> noArgs was being incremented in the code above.  This was in the 
> hdfsJniHelper.c file, in the getJNIEnv function.



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