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https://issues.apache.org/jira/browse/HADOOP-12550?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14990649#comment-14990649
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Ivan Mitic commented on HADOOP-12550:
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Hi [~cnauroth],
Interesting problem!
I reviewed docs for Linux rename and Windows MoveFileEx with the
MOVEFILE_REPLACE_EXISTING flag, and indeed they seem compatible (noticed only
one semantic difference when the target folder already exists and it's empty).
Seems to me like the right fix. I am +1 on the patch. One minor comment, please
include an inline code comment providing the background on
MOVEFILE_REPLACE_EXISTING flag.
Before you commit, would you be able to validate that existing
Common/Hdfs/MR/Yarn tests did not regress on Windows?
> NativeIO#renameTo on Windows cannot replace an existing file at the
> destination.
> --------------------------------------------------------------------------------
>
> Key: HADOOP-12550
> URL: https://issues.apache.org/jira/browse/HADOOP-12550
> Project: Hadoop Common
> Issue Type: Bug
> Components: native
> Environment: Windows
> Reporter: Chris Nauroth
> Assignee: Chris Nauroth
> Attachments: HADOOP-12550.001.patch
>
>
> {{NativeIO#renameTo}} currently has different semantics on Linux vs. Windows
> if a file already exists at the destination. On Linux, it's a passthrough to
> the [rename|http://linux.die.net/man/2/rename] syscall, which will replace an
> existing file at the destination. On Windows, it's a passthrough to
> [MoveFile|https://msdn.microsoft.com/en-us/library/windows/desktop/aa365239%28v=vs.85%29.aspx?f=255&MSPPError=-2147217396],
> which cannot replace an existing file at the destination and instead
> triggers an error. The easiest way to observe this difference is to run the
> HDFS test {{TestRollingUpgrade#testRollback}}. This fails on Windows due to
> a block recovery after truncate trying to replace a block at an existing
> destination path. This issue proposes to use
> [MoveFileEx|https://msdn.microsoft.com/en-us/library/windows/desktop/aa365240(v=vs.85).aspx]
> on Windows with the {{MOVEFILE_REPLACE_EXISTING}} flag.
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