Store multiple values in a declarative array, including the error-code of a command. (Note that in most cases you want to use $? directly or $PIPESTATUS if you have a pipe to get just the error-code.) Needs bash-version > 4.

declare -A array=$(the php-way)

#!/bin/bash

# generates a string in the form of an array-declaration and puts it into declare -A
declare -A exit_status=$(echo -n "( \
[output]=\"" ; cat /no/such/file 2>&1 ; echo -en "\"
[errno]=$?
)")

# to test it:
echo error ${exit_status[errno]}: ${exit_status[output]} >/dev/stderr
exit ${exit_status[errno]}