Shell Scripting

Problem using sed

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Join Date: Mar 2008

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guest7

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Junior Poster

Problem using sed

Oct 17th, 2009

Hi,

I am trying to replace the old_string with the new_string using sed.
But i am unable to do it using the following script.

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 Shell Scripting Syntax (Toggle Plain Text) 
#!/bin/sh
 
old_string="p cnf 10 20"
new_string="p cnf 98 99"
 
sed -e 's/old_string/new_string/' file1.txt > file2.txt
#!/bin/sh

old_string="p cnf 10 20"
new_string="p cnf 98 99"

sed -e 's/old_string/new_string/' file1.txt > file2.txt

Contents of file1.txt

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p cnf 10 20
1 2 3
4 5 6
8 9 10
11 12 30
p cnf 10 20
1 2 3
4 5 6
8 9 10
11 12 30

Any help is appreciated.

Last edited by guest7; Oct 17th, 2009 at 9:34 pm.

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Aia

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Oct 17th, 2009

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sed -e "s/$old_string/$new_string/" file1.txt > file2.txt

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Join Date: Nov 2009

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chrislee.980 chrislee.980 is offline

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Newbie Poster

31 Days Ago

I have a little sed problem which I can't seem to figure out:
I would like to concatenate the next line of a file to the current line if the current line doesn't end in ;
I tried the next command but it doesn't seem to work:

sed '/[^;]$/{N;s/\n//;}'

Any ideas?

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