how to replace value of 4.1.0.1.22 to 4.1.0.0.22 using shell script

amit_pansuria · 08-06-2008, 09:20 AM

helo ,

I have one requirement in my shell script. that
in my version.txt I have write down

4.1.0.1.22

Now I want to read this number and changes this number to 4.1.0.0.22 and
store it in seperate variable. original file number need not be changed.

Regards,
Amit

colucix · 08-06-2008, 09:49 AM

If the original version number is stored in a variable, you can use substring replacement. For example

Code:

old_version=4.1.0.1.22
new_version=${old_version/1.22/0.22}

otherwise use sed, as in

Code:

new_version=$(echo 4.1.0.1.22 | sed s/4[.]1[.]0[.]1[.]22/4.1.0.0.22/}

the square brackets around the dots in the pattern are character lists: this is a way to make sed interpret a literal dot, otherwise it has the special meaning of any single character and the strings 4c1.0d1.22 or 4.1e0.1922 match as well.

ta0kira · 08-06-2008, 08:04 PM

I think escaping "." with "\" is preferable and less confusing. It does require the statement to be in either '' or "", though.
ta0kira

ghostdog74 · 08-06-2008, 08:30 PM

if you always know where you want to change

Code:

awk -F"." ' $4=0;$1=$1' OFS="." file