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How to replace characters in a file?

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# 1  
Old 06-24-2013
How to replace characters in a file?
Hi Gurus,

I need replace some charactors in a file.
in following example. I need replace from 4th charactor to 6th charactor with x in each line.
Code:
abcdefghijklmn
123456789011

excepted result:
Code:
abcxxxghijklmn
123xxx789011

Thanks in advance.
# 2  
Old 06-24-2013
Using awk substr function:
Code:
awk '{print substr($0,1,3)"xxx"substr($0,7)}' file

This User Gave Thanks to Yoda For This Post:
ken6503
# 3  
Old 06-24-2013
Quote:
Originally Posted by Yoda
Using awk substr function:
Code:
awk '{print substr($0,1,3)"xxx"substr($0,7)}' file

It works great. Thanks

SmilieSmilieSmilie
# 4  
Old 06-25-2013
With sed:
Code:
sed 's/.../xxx/2' file

This User Gave Thanks to Scrutinizer For This Post:
ken6503
# 5  
Old 06-25-2013
Substitute after 3 characters
Code:
sed 's/\(.\{3\}\).../\1xxx/' file

This User Gave Thanks to MadeInGermany For This Post:
ken6503
# 6  
Old 06-26-2013
Thanks Guys,
All suggestions are work fine.
I have one more quesiton, if I have 50 or more charactor's need to be replaced, if there any easy way to avoid to type 50 'X'?

Thanks in advance
# 7  
Old 06-26-2013
Try:
Code:
awk '{for(i=s+1; i<=w+s; i++) $0=substr($0,1,i-1) "x" substr($0,i+1)}1' s=3 w=50 file

or
Code:
awk -v s=3 -v w=50 'BEGIN{r=sprintf("%0" w "s",x); gsub(0,"x",r)} {print substr($0,1,s) r substr($0,s+w+1)}' file

gawk and some other awks:
Code:
awk '{for(i=s+1; i<=w+s; i++) sub(/./,"x",$i)}1' s=3 w=50 FS= OFS= file

gawk only:
Code:
gawk -v s=3 -v w=50 'BEGIN{FIELDWIDTHS=s " " w " " 1000} {gsub(/./,"x",$2)}1' OFS= file

with bash, ksh93:
Code:
xout=$(printf "%050s" ""); sed "s/\(...\).\{50\}/\1${xout//0/x}/" file

Last edited by Scrutinizer; 06-26-2013 at 02:53 PM..
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