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# 1  
Old 09-01-2009
Question modifying file using script

Hi,

I am new to shell programming, and want to know is it possible to change the contents of file using script?

for example, if want to search 2 words and want to replace these words with 2 new words.

Regards,

Manoj
# 2  
Old 09-01-2009
Yes, it is posssible

Eg

file.txt
aaa
bbb
ccc

Now if i want to replace bbb with ddd ,use

Code:
sed 's/bbb/ddd/' file.txt > file1.txt

Note you can't directly modify a file, you have to redirect it to other file
# 3  
Old 09-01-2009
Code:
Note you can't directly modify a file, you have to redirect it to other file

You can using perl one liner.
# 4  
Old 09-01-2009
Quote:
Originally Posted by sarbjit
Note you can't directly modify a file, you have to redirect it to other file
you can... but not with "sed" which is the "stream editor". but you can use "ed" to alter a file directly. afaik it uses the same syntax as "sed"!
# 5  
Old 09-01-2009
You can edit a file inplace with sed, without redirection with the '-i' switch if you have it...

Code:
sed -i~ 's/bbb/ddd/' 'file'

-Enjoy
fh : )_~

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