#creates a new file descriptor 3 that redirects to 1 (STDOUT)
exec 3>&1
# Run curl in a separate command, capturing output of -w "%{http_code}" into HTTP_STATUS
# and sending the content to this command's STDOUT with -o >(cat >&3)
HTTP_STATUS=$(curl -w "%{http_code}" -o >(cat >&3) 'http://example.com')