Using sed/awk to replace a string at a given position in
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Now I want to replace a pattern of 9 digits at the 6 th position with another patten,
say 700044001 with 700020050
I need to replace only if 700044001 occurs at 6th position, other wise no changes need be done.
Problem is that I dont want to change the first pattern into second pattern whenever it occurs. I want it to change it only when it occurs at the 6th column
sed -e 's/firstpattern/secondpattern/g' file
will replace all the occurences of first pattern with second pattern, I believe, and I dont want that to happen.
Since this is not a file separated by spaces as separate columns, I believe I cannot also use awk using $1, $2 etc.
Problem is that I dont want to change the first pattern into second pattern whenever it occurs. I want it to change it only when it occurs at the 6th column
sed -e 's/firstpattern/secondpattern/g' file
will replace all the occurences of first pattern with second pattern, I believe, and I dont want that to happen.
Since this is not a file separated by spaces as separate columns, I believe I cannot also use awk using $1, $2 etc.
Read my post more carefully...
Quote:
The general form you are looking for is: sed '/pattern/s/string/newstring/'
Use "pattern" to decide which lines to modify. When sed finds "pattern", then it does the substitution according to what follows the "s" command
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