#!/opt/homebrew/bin/bash bash CORE_PORT=8333 CORE_RPCPORT=8332 arguments="" for env in "${!CORE_@}" do value=${!env} uppercase_flag=${env#CORE_} lowercase_flag=${uppercase_flag,,} arguments="${arguments} -${lowercase_flag,,}=${!env}" done echo $arguments # -port=8333 -rpcport=8332