#!/usr/bin/env sh
# check for minimum version being fulfilled
# Argument $1 must be the target version
# Argument $2 must be the program version to check for
#
# Versions must be stripped of any leading labels or 'v', 'version' prefix
# and will only be checked for their numeric contents.
# 1.0 2.13 5.1.25 are all valid version numbers.
#
# Can also be used to check the correct sorting of an arbitrary number of
# versions, if invoked like:
# version_at_least 1.0 2.0 2.2 3.13
# If versions are out of order will return false.
#
# Further reading:
# https://unix.stackexchange.com/questions/285924/how-to-compare-a-programs-version-in-a-shell-script
# https://stackoverflow.com/questions/4493205/unix-sort-of-version-numbers

printf '%s\n' "$@" | sort -t. -n -k1,1 -k2,2 -k3,3 -k4,4 --check=quiet