#! /bin/sh -e cmd="$1" runtime="$2" oldversion="$3" newverison="$4" if which python >/dev/null 2>&1 && which pycentral >/dev/null 2>&1; then pycentral rtinstall --ignore-errors=yes $runtime else echo >&2 "python or pycentral not found in $(basename $0) hook." exit 1 fi