Exit Codes & JSON Output

mdocker is built to be scriptable: predictable exit codes and machine-readable output where it matters.

Exit codes

Code	Meaning
`0`	Success.
`1`	Generic error (an internal `die`).
`2`	Port-conflict pre-flight failed — no free replacement port could be found.

Exit code 2 is specific to up: if the pre-flight cannot find a free host port, the command aborts with 2 rather than starting a broken stack. To handle it, either free the port, or re-run with --auto-remap-ports (remap automatically) or --no-port-check (skip the check).

if mdocker up aurora; then
  echo "started"
elif [ $? -eq 2 ]; then
  echo "port conflict — retrying with auto-remap"
  mdocker up aurora --auto-remap-ports
fi

JSON output

Read-only verbs accept --json, which emits machine-readable output you can pipe into jq. The flag may be placed before the verb (mdocker --json git info aurora).

mdocker --json ls | jq -r '.[].name'
mdocker inspect aurora --json | jq '.[].connection'
mdocker git info aurora --json | jq '.branch, .dirty'

Verbs that support --json include ls, inspect, health, stats, edge status, edge logs, config show, config domain list, git info, share ls, profile list, profile validate, db list, terminal list and terminal tools.

MultiDocker · Coding9 GmbH