Anyone for scripting?

[Adam Noble]

I imagine one of you guys will be able to solve my problem very quickly (i hope). I need a script to take a line of input and change the 5-7th character of that input and replace it with 3 alternate characters. I thought tr may be the tool to do this however can't seem to determine the specific format.

[Robin Wakefield]

Hi Adam,

Using sed:

% echo abcdefghijkl | sed 's/\(^....\)...\(.*\)/\1zzz\2/'
abcdzzzhijkl
%

rgds, Robin

[G. Vrijhoeven]

Hi,

for i in `cat file`
do
VAR=`echo $i | cut -c 5-7`
echo $i | sed 's/'$VAR'//'
done

Gideon

[Jean-Louis Phelix]

Hi,

sed 's;^\(....\)...;\1ABC;' file

should replace 5th, 6th and 7th chars to ABC.

Regards

[Adam Noble]

Thanks guys much appreciated, even tho the sed command looks a little complex, I think I see what going on.

[Marcin Piwko]

This is better than sed:

nawk '{ print substr($0, 1, 4) "XXX" substr($0, 8) }' filename

Where XXX are your alternate characters.

[Jean-Louis Phelix]

Perhaps awk would be more 'readable':

awk '{
printf "%s%s%s\n", substr($0,1,4),
"ABC",
substr($0, 8)}'
}' file

will do the same ...

Regards.