dig -version (return code: 0)
DiG 9.10.3-P4-Ubuntu
dig --help (return code: 1)
Invalid option: --help
Usage: dig [@global-server] [domain] [q-type] [q-class] {q-opt}
{global-d-opt} host [@local-server] {local-d-opt}
[ host [@local-server] {local-d-opt} [...]]
Use "dig -h" (or "dig -h | more") for complete list of options