Bsrgvty

I need a script to check if yad (and other programs) version number is >= to a specific number. For example I have:

$ yad --version
0.40.0 (GTK+ 3.24.8)

$ gedit --version
gedit - Version 3.32.0

$ bash --version
GNU bash, version 5.0.3(1)-release (x86_64-pc-linux-gnu)
Copyright (C) 2019 Free Software Foundation, Inc.

• For yad new features are added between Ubuntu 16.04 and 19.04


• For gedit the ability to pass Window geometry is lost in newer versions


• 
  bash complicates tests as the version number is in the middle of the first line.

An environment variable will not exist for all programs like bash has:

$ echo $BASH_VERSION
5.0.3(1)-release

You might want to try GNU sort's -V (--version-sort), along with -C (--check=quiet):

$ echo $BASH_VERSION
4.4.20(1)-release

then to return 0 (true) if the version is at least the given one and 1 (false) otherwise:

$ printf '%sn%sn' "$BASH_VERSION" "4.3" | sort -rVC ; echo $?
0

$ printf '%sn%sn' "$BASH_VERSION" "4.4.20(2)" | sort -rVC ; echo $?
1

I developed a script that draws on answers in Stack Overflow. One of those answers led to a Dell Employee writing version number comparisons in 2004 for the DKMS application.

Sample Tests

$ testver yad 0.40.0; echo $?
0
$ testver yad 0.41.0; echo $?
1
$ testver bash 5.0.3; echo $?
0
$ testver bash 5.0.4; echo $?
1
$ testver gedit 3.32.0; echo $?
0
$ testver gedit 4.32.0; echo $?
1
$ testver iwconfig 30; echo $?
0
$ testver iwconfig 31; echo $?
1

Real life application

if testver gnome-shell 3.32.0 ; then
 # returns 0 version 3.32.0 and greater geometry not supported.
 nohup gedit $@ &>/dev/null &
else
 # returns 1 version less than 3.32.0 so geometry supported.
 nohup gedit -g 1300x840+4565+2345 $@ &>/dev/null &
fi

The code

The bash script below needs to be marked as executable using the command chmod a+x script-name. I'm using the name /usr/local/bin/testver:

#!/bin/bash

# NAME: testver
# PATH: /usr/local/bin
# DESC: Test a program's version number >= to passed version number
# DATE: May 21, 2017. Modified August 5, 2019.

# CALL: testver Program Version

# PARM: 1. Program - validated to be a command
# 2. Version - validated to be numberic

# NOTE: Extracting version number perl one-liner found here:
# http://stackoverflow.com/questions/16817646/extract-version-number-from-a-string

# Comparing two version numbers code found here:
# http://stackoverflow.com/questions/4023830/how-compare-two-strings-in-dot-separated-version-format-in-bash

# Map parameters to coder-friendly names.
Program="$1"
Version="$2"

# Program name must be a valid command.
command -v $Program >/dev/null 2>&1 || echo "Command: $Program not found. Check spelling."; exit 99; 

# Passed version number must be valid format.
if ! [[ $Version =~ ^([0-9]+.?)+$ ]]; then
 echo "Version number: $Version has invalid format. Aborting.";
 exit 99
fi

InstalledVersion=$( "$Program" --version | perl -pe '($_)=/([0-9]+([.][0-9]+)+)/' )

# Perl command doesn't work for non-decimal version numbers
[[ "$InstalledVersion" == "" ]] && 
 InstalledVersion=$( "$Program" --version | head -n1 | tr -dc '0-9')

if [[ $InstalledVersion =~ ^([0-9]+.?)+$ ]]; then
 l=($InstalledVersion//./ )
 r=($Version//./ )
 s=$#l[@]
 [[ $#r[@] -gt $#l[@] ]] && s=$#r[@]

 for i in $(seq 0 $((s - 1))); do
 # echo "Installed $l[$i] -gt Test $r[$i]?"
 [[ $l[$i] -gt $r[$i] ]] && exit 0 # Installed version > test version.
 [[ $l[$i] -lt $r[$i] ]] && exit 1 # Installed version < test version.
 done

 exit 0 # Installed version = test version.
else
 echo "Invalid version number: $InstalledVersion found for command: $Program"
 exit 99
fi

echo "testver - Unreachable code has been reached!"
exit 255

You can use dpkg --compare-versions. Usage example:

$ dpkg --compare-versions 4.0 lt 5.0 && echo true
true

This returns "true" because version 4.0 is less than ("lt") version 5.0.

On the other hand the following does not return anything:

$ dpkg --compare-versions 4.0 gt 5.0 && echo true

This is because version 4.0 is not greater ("gt") than 5.0.

Comparison operators for dpkg --compare-versions are:

• 
  lt le eq ne ge gt (treat empty version as earlier than any
  version);


• 
  lt-nl le-nl ge-nl gt-nl (treat empty version as later
  than any version);


• 
  < << <= = >= >> > (only for compatibility with control file syntax).