Environment

tmux exposes two environment APIs. Process variables such as TMUX and TMUX_PANE let code inside a pane identify its server and pane. The server also stores variables through set-environment and show-environment for new processes to inherit. Like the tables in Options and hooks, this persistent store has explicit scopes.

Locating yourself from inside a pane¶

Inside a pane, TMUX contains <socket path>,<server pid>,<session id>, and TMUX_PANE contains the pane ID, such as %1. Use these variables to locate the current tmux objects. Select the object your operation needs:

Server: Server.FromEnvironment(env)

Session: Session.FromEnvironmentAsync()

Window: Window.FromEnvironmentAsync()

Pane: Pane.FromEnvironmentAsync()

Examples¶

Server server = Server.FromEnvironment(null);
Session session = await Session.FromEnvironmentAsync();
Window window = await Window.FromEnvironmentAsync();
Pane pane = await Pane.FromEnvironmentAsync();

Environment lookup requires valid tmux targeting variables. If your process can run outside tmux, handle that case before using the result.

Handle TmuxObjectNotFoundException when the environment cannot identify an object.

tmux's own environment variable store¶

Like Options and hooks, tmux's persistent environment store has global and per-session scopes. It is read with show-environment and updated with set-environment. Newly spawned processes inherit it; existing processes retain their own environments.

Set: server.Environment.SetAsync(name, value), session.Environment.SetAsync(...)

Read all: server.Environment.GetAllAsync()

Unset: server.Environment.UnsetAsync(name), .RemoveAsync(name)

Examples¶

await server.Environment.SetAsync("EDITOR", "vim");
await session.Environment.SetAsync("EDITOR", "hx");
await session.Environment.GetAllAsync();

set-environment writes a value. Its -u flag removes the entry, while -r marks the variable for exclusion from new processes, including values tmux inherited at startup. The listing retains an excluded variable as -NAME.

Use .UnsetAsync for -u, or .RemoveAsync for -r.