-releasearchive=${1:?"provide path to release archive"}
-targetreleasearchive="${prefix}$(basename "${releasearchive}")"
+releasearchive="${1:?"provide path to release archive"}"
+releasearchive="$(readlink -f "${releasearchive}")" # convert to absolute path
+test -f ${releasearchive} || error "file ${releasearchive} doesn't exist"
+releasename="${prefix}$(basename "${releasearchive}")"