How to check if a program version is equal to or smaller than x

Question

I'm writing a shell script that has to know if a certain program version is less or equal to version x.xx.xx

here is an example script to try and explain what I want to do:

#!/bin/bash
APPVER="some command to output version | grep x.xx*"
if [[ "$APPVER" is smaller or equal to "x.xx*" ]]; then
    do something
else
    do something else
fi

is there a way to do that? I found ways to compare numbers, but they won't work with version numbers. I need a solution that uses no or as little as possible programs.

any help is appreciated!

Welcome, when you say "app", what exactly do you mean? Packages? — schrodingerscatcuriosity, Feb 02 '21 at 21:55
some program app, it doesn't really matter. for the code I have a app/program output a version for example 1.5.30 and I need to check if its less or equal to 1.6 — Itai Nelken, Feb 02 '21 at 21:57

score 3 · Answer 1 · answered Feb 02 '21 at 23:02

3

In bash, you can do it with printf -v:

vercomp(){
   local a b IFS=. -; set -f
   printf -v a %08d $1; printf -v b %08d $3
   test $a "$2" $b
}
if vercomp 2.50.1 &lt; 2.6; then
   echo older
else
   echo newer
fi

answered Feb 02 '21 at 23:02

can you explain what exactly your code is doing please? – Itai Nelken Feb 03 '21 at 07:32
It implements a bash function which compares two version strings, without using external commands like sort or spawning subprocesses with $(...). It's limited to plain version strings like 5.8.12 or 12.3.08.1; it will not work with 2.5.3-alpha1 or version/patchlevel combos. It's also bash-only, it doesnt't work with a standard shell. – Feb 03 '21 at 10:49
this answer helped me a lot, but I'm marking the other one as the answer because its simpler. in real world usage this answer is more useful though. – Itai Nelken Feb 04 '21 at 19:46

score 3 · Accepted Answer · answered Feb 02 '21 at 23:28

3

If you have GNU sort, use its version comparison mode.

if { echo "$APPVER"; echo "x.y.z"; } | sort --version-sort --check; then
  echo "App version is x.y.x or less"
fi

answered Feb 02 '21 at 23:28

Gilles 'SO- stop being evil'

829,060

when testing your code like this:

APPVER="1.13"

if { echo "$APPVER"; echo "1.12.9"; } | sort --version-sort --check; then
  echo "App version is 1.12.9 or less"
fi

I get this error: sort: -:2: disorder: 1.12.9 but it works when using it like this:

APPVER="1.12.2"

if { echo "$APPVER"; echo "1.12.9"; } | sort --version-sort --check; then
  echo "App version is 1.12.9 or less"
fi

do you know why?

– Itai Nelken Feb 03 '21 at 07:31

1.13 isn't 1.12.9 or less, but 1.12.2 is, so what's the problem? – Gilles 'SO- stop being evil' Feb 03 '21 at 09:46
I think I found what was wrong, there is no else so I got a error, your script worked perfectly fine, Thanks! – Itai Nelken Feb 03 '21 at 11:16

How to check if a **program** version is equal to or smaller than x

2 Answers2

How to check if a program version is equal to or smaller than x