Cancel a control wait

Cancel a control signal wait and check that the connection remains open. Leaving the ownership blocks then closes the control clients and the private tmux server.

Setup¶

Julia 1.13.0, Git, POSIX shell and tmux on Linux. Start in an empty directory. The following commands run in a POSIX shell.

Fetch the library revision used by this program.

$ git init -q source
$ git -C source fetch -q --depth=1 \
  https://github.com/libtmux/libtmux-julia.git \
  6f62bd72cb8d99f3759ca5e2cc3591165a03c768
$ git -C source checkout -q --detach FETCH_HEAD

Program¶

Save this complete program as control_cancel.jl.

using LibTmux

function main()
    with_server(; tmux=get(ENV, "LIBTMUX_TEST_TMUX", "tmux")) do server
        session = new_session(server; name="control", command=["/bin/cat"])
        open_control(server, session) do connection
            signal = control_signal(connection)
            token = CancellationToken()
            waiting = Threads.@spawn try
                wait(signal; cancel=token)
            catch error
                error
            end
            cancel!(token)
            @assert fetch(waiting) isa RequestCancelled
            @assert isopen(connection)
        end
        @assert isempty(clients(snapshot(server)))
    end
    println("Cancelled the wait and closed both owned control clients")
end

main()

The task catches its cancellation error so the caller can assert that it is SRequestCancelled. Cancelling the wait does not close the connection. After fopen_control returns, the snapshot must contain no attached clients; fwith_server then stops the daemon.

Run¶

$ unset TMUX TMUX_PANE
$ export ENV=/dev/null BASH_ENV=/dev/null SHELL=/bin/sh
$ julia --startup-file=no --project=source control_cancel.jl

Expected output:

Cancelled the wait and closed both owned control clients

Related APIs¶

• fopen_control
• SCancellationToken
• fcancel!
• Ownership

Source and verification¶

The complete program comes from examples/control_cancel.jl. The verification runner executes these displayed files and setup commands unchanged, checks the output, and checks that the program stopped its private tmux server. Each example runs independently.