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Date: Wed, 31 Oct 2012 16:31:04 -0500
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Subject: Re: A question about reading one block
From: Vivi Lang <sqlxweiwei@gmail.com>
To: hdfs-dev@hadoop.apache.org
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Please ignore the previous email which I did not describe the problem
clearly.

On Wed, Oct 31, 2012 at 3:05 PM, Vivi Lang <sqlxweiwei@gmail.com> wrote:

> Hi, thks for the replying.
>
> Is there any function can help me to create a InputStream for a certain
> Block which stored in a certain datanode
> Thanks,
>
> On Sat, Oct 27, 2012 at 9:41 PM, Harsh J <harsh@cloudera.com> wrote:
>
>> Vivi,
>>
>> Assuming you know how to get the block info out of a file's metadata,
>> opening a file for read (with FileSystem.open API, etc.) with an
>> offset and length set to to match that of a block, will open and read
>> only that block.
>>
>> On Sat, Oct 27, 2012 at 2:19 AM, Vivi Lang <sqlxweiwei@gmail.com> wrote:
>> > Hi guys,
>> >
>> > I am writing a program which need the data of several specific blocks (I
>> > know the blockinfo of those blocks), if I use the Hadoop 0.20, is there
>> > any  funtion which can help me to retrieve the content of block?
>> >
>> > Thanks,
>> > Vivi
>>
>>
>>
>> --
>> Harsh J
>>
>
>

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