From: Avdi Grimm <avdi@...>
Date: 2008-04-29T01:47:47+09:00
Subject: Re: Transpose a large file(>2GB)

On Sun, Apr 27, 2008 at 6:32 AM, Ams Lo <rgowka1@gmail.com> wrote:
> Hi -
>
>  What is the fast and ruby way to transpose a large file(>2GB)??

fseek to the end of the file.  fseek backwards by a nice round number
like 4k.  Read in that exact number of bytes.  Transpose it.  Write
the transposed block to your output file.  Then fseek back 2*4k.
Read, transpose, write.  fseek back 3*4k.  Etc.  Rinse and repeat to
the beginning of the file.

-- 
Avdi

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