# Socket and servers

Source: https://libtmux.org/en/rs/latest/topics/socket-and-servers/

> Select a server socket, check liveness, and detect a replacement daemon.

A tmux server is selected by its Unix-domain socket. Use different sockets for
independent servers, such as a development session and an isolated test server.
Choose the default socket, a named socket (`-L`), or an explicit path (`-S`).

## Naming a server

[`Server::new()`](<https://libtmux.org/en/rs/latest/reference/server-server-new/>) selects the default socket. Use
[`Server::builder().socket_name("work").build()?`](<https://libtmux.org/en/rs/latest/reference/server-server-builder/>) for a named socket or
[`Server::builder().socket_path(path).build()?`](<https://libtmux.org/en/rs/latest/reference/server-server-builder/>) for an explicit path.

```rust
let named = libtmux::Server::builder().socket_name("work").build()?;
```

Choose either a socket name or a socket path. tmux uses `TMUX_TMPDIR` to
resolve the directory for default and named sockets.

## Is the server actually there?

A server handle does not prove that the target server is running. Use a liveness
check when your program needs to distinguish a live server from an unavailable
socket:

[`Server.is_alive`](<https://libtmux.org/en/rs/latest/reference/server-server-is_alive/>) returns a boolean. Use [`Server.check_alive`](<https://libtmux.org/en/rs/latest/reference/server-server-check_alive/>) when
you also need to distinguish a failed check from a server that is not alive.

```rust
if server.is_alive().await {
    server.sessions().await?;
}
```

[`is_alive()`](<https://libtmux.org/en/rs/latest/reference/server-server-is_alive/>) returns a boolean. Use [`check_alive()`](<https://libtmux.org/en/rs/latest/reference/server-server-check_alive/>) when you need failure details.

## Killing a server, and telling two apart

Killing a server ends all its sessions. Use this only for a server your program
owns; for narrower cleanup, kill the session or pane you created.

Call [`server.kill().await?`](<https://libtmux.org/en/rs/latest/reference/server-server-kill/>) and handle a cleanup failure before returning.

A restarted server can reuse a socket path while having different state. Do
not treat a matching path as proof that a cached object still exists.