Problem with Bash output redirection

Posted by Aman Jain on Stack Overflow See other posts from Stack Overflow or by Aman Jain
Published on 2008-09-23T19:29:26Z Indexed on 2010/03/25 4:03 UTC
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linux

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bash

I was trying to remove all the lines of a file except the last line but the following command did not work, although file.txt is not empty.

$cat file.txt |tail -1 > file.txt

$cat file.txt

Why is it so?

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