Extract version number from file in shell script

Question

I'm trying to write a bash script that increments the version number which is given in

{major}.{minor}.{revision} 

For example.

1.2.13 

Is there a good way to easily extract those 3 numbers using something like sed or awk such that I could increment the {revision} number and output the full version number string.

Answer 1

$ v=1.2.13 $ echo "${v%.*}.$((${v##*.}+1))" 1.2.14 

---

$ v=11.1.2.3.0 $ echo "${v%.*}.$((${v##*.}+1))" 11.1.2.3.1 

---

Here is how it works:

The string is split in two parts.

• the first one contains everything but the last dot and next characters: ${v%.*}
• the second one contains everything but all characters up to the last dot: ${v##*.}

The first part is printed as is, followed by a plain dot and the last part incremented using shell arithmetic expansion: $((x+1))

Answer 2

Pure Bash using an array:

version='1.2.33' a=( ${version//./ } )                   # replace points, split into array ((a[2]++))                              # increment revision (or other part) version="${a[0]}.${a[1]}.${a[2]}"       # compose new version