# Session commands (/docs/v0.4/cli/sessions)



A session runs in its own process. These commands start one, join one, leave
one, and end one. The concepts are on
[Attach and detach](/docs/v0.4/using/attach-and-detach).

## Start [#start]

```bash
koshi                        # start and attach this terminal
koshi --profile dev          # start from profile/dev.kdl
koshi --headless             # start with nothing attached
koshi --headless --allow-other-users   # the same, open to this machine's other users
```

`--allow-other-users` goes only with `--headless`. That session serves the
other users of this machine for its whole life, whatever `koshi.kdl` says. See
[Sharing with other users](/docs/v0.4/using/other-users).

`--headless` prints the session id and returns to the shell. Nothing is drawn.

```text
koshi --headless
[SESSION ID]: session-3f2a…
```

## `attach` [#attach]

```bash
koshi attach                 # pick from the running sessions
koshi attach amber-fox       # by name
koshi attach session-3f2a…   # by id
koshi attach --remote work quiet-heron   # on another machine
```

Run outside koshi, `attach` opens that session in this terminal. Run inside a
koshi pane, it **moves** this terminal to the named session instead.

With no argument, koshi lists this machine's sessions and the sessions on every
saved server that answered, numbers them, and reads your answer. A session on a
saved server carries `(remote: <server>)`:

```text
koshi attach
1) amber-fox session-3f2a…
2) quiet-heron session-91c4… (remote: work)
attach to which session? [1-2]
```

A listing of exactly one session, on this machine, is attached without asking.
Every other listing asks, one session on a saved server included, whose prompt
reads `attach to which session? [1]`.

## `detach` [#detach]

```bash
koshi detach                       # inside a pane: this terminal
koshi detach client-0e5a…          # a client id
koshi detach session-3f2a…         # that session's client, by id
koshi detach amber-fox             # the same, by session name
koshi detach --all amber-fox       # every terminal of that session
```

Detaching leaves the session running with its panes untouched. Bare
`koshi detach` works only inside a koshi pane. Outside one, name the target: a
client id, a session id, or a session name.

A session left with no terminal keeps running, unless `auto-close-session` is
`#true` in the `koshi.kdl` the session read when it started.

## `kill-session` [#kill-session]

```bash
koshi kill-session                 # the only running session
koshi kill-session amber-fox       # by name
koshi kill-session session-3f2a…   # by id
```

Ends the session and everything in it, whatever is attached. An id goes
straight to that session with no lookup. With no argument it works only when
exactly one session is running.

`kill-session` skips the wait that `auto-close-session` gives programs to stop.

| Exit code | Meaning                                 |
| --------- | --------------------------------------- |
| `3`       | Unknown session name or id              |
| `4`       | The control socket could not be reached |

## `list-sessions` [#list-sessions]

```bash
koshi list-sessions
koshi list-sessions --format json
```

Prints session ids and names, with a `server` column: `local` for a session on
this machine, else the saved server it runs on. A bare `koshi list-sessions`
sweeps every saved server and appends what answered;
`koshi list-sessions --remote <server>` lists that one server's sessions alone.

A server that refused the saved secret, and a server that did not answer, are
named on standard error and their sessions are left out.

See [Discovery](/docs/v0.4/cli/discovery) for tabs, panes, and clients.

## Summary [#summary]

| Command                                    | Result                                                 |
| ------------------------------------------ | ------------------------------------------------------ |
| `koshi --headless`                         | Start a session with nothing attached and print its id |
| `koshi list-sessions`                      | List session ids and names                             |
| `koshi attach [NAME_OR_ID]`                | Attach this terminal to that session                   |
| `koshi detach [CLIENT_OR_SESSION]`         | Detach one terminal; the session keeps running         |
| `koshi detach --all [NAME_OR_ID]`          | Detach every terminal of that session                  |
| `koshi kill-session [NAME_OR_ID]`          | End that session, or the only running one              |
| `koshi attach --remote <SERVER> [SESSION]` | Attach to a session on another machine                 |