Text substitution (reading from file and saving to the same file) on linux with sed...

Posted by Roger on Stack Overflow See other posts from Stack Overflow or by Roger
Published on 2011-06-26T13:47:57Z Indexed on 2011/06/27 0:22 UTC
Read the original article Hit count: 241

Filed under:

bash

|

unix

|

sed

|

cli

I want to read the file "teste", make some "find&replace" and overwrite "teste" with the results. The closer i got till now is:

$cat teste
I have to find something
This is hard to find...
Find it wright now!

$sed -n 's/find/replace/w teste1' teste

$cat teste1
I have to replace something
This is hard to replace...

If I try to save to the same file like this:

$sed -n 's/find/replace/w teste' teste

or:

$sed -n 's/find/replace/' teste > teste

The result will be a blank file...

I know I am missing something very stupid but any help will be welcome.

UPDATE: Based on the tips given by the folks and this link: http://idolinux.blogspot.com/2008/08/sed-in-place-edit.html here's my updated code:

sed -i -e 's/find/replace/g' teste

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