avr ports

Lists the ports the current environment forwards to your computer, the address to open each at, and the Linux process listening on it. With --all, it does the same for every running environment.

  1. Help
  2. Examples
  3. What it does
  4. Exit status
  5. Errors
  6. See also

Help

This is exactly what avr help ports or avr ports --help prints.

Usage:
  avr [selector flags] ports [--all]

List the ports the selected environment forwards to this computer, with the address to open each at and the Linux process listening on it where avar can tell. Ports that are listening in Linux but cannot be reached from this computer are listed with the reason. The environment is never started to find out.

Flags:
  --all   list the ports of every running Linux environment avar manages

Selector flags such as --arch and --distro must come before the command; run `avr --help` to see them.

Examples

avr ports                     # the environment this directory uses
avr --distro fedora ports     # this project's Fedora environment
avr ports --all               # every running environment

What it does

avr ports reads; it never creates or starts an environment. When the environment does not exist or is not running, it says so, and how to start it, and exits 0.

For a running environment it prints a table:

Ubuntu 24.04 · arm64 forwards 1 port to this computer:

  PORT  ADDRESS                PROCESS
  3000  http://localhost:3000  node server.js (pid 4121)

PORT and ADDRESS are where to reach the port on your computer. PROCESS is the command line and process ID listening in Linux, where avar can tell, and — where it cannot.

A port that is listening in Linux but cannot be reached from your computer is listed below the table under Listening in Linux but not reachable from this computer:, with the reason. On macOS the reason is Lima’s, for example that the port on your Mac is already in use by another program. On Windows it usually means localhost forwarding is turned off in .wslconfig, or another program holds the port.

When nothing in the environment is listening, avr ports says so. A server you start with avr <command> appears once it is listening.

With --all, selector flags make no difference: every running environment avar manages is listed, one after another. If avar cannot read one of them, it says so in that environment’s place, lists the rest, and exits 1 at the end.

Exit status

Status When
0 Listed, including when the environment is not running or nothing is listening
1 avar could not read an environment’s ports, or reach the backend
2 An argument other than --all, or an unsupported environment

Errors

avr: `avr ports` does not understand "<arg>": it takes no arguments, or --all to list the ports of every running Linux environment

Exit status 2.

avr: listing the ports forwarded from <environment>: <cause>; `avr status` shows whether the environment is healthy

Exit status 1.

See also