(define (i3-command msg)
  (let ((ipc (socket af/unix sock/stream)))
    (socket-connect ipc (unix-address (i3-socket-path)))
    (socket-send-all ipc (i3-format-ipc-message msg 0))
    (socket-receive ipc (string-length "i3-ipc"))
    (let ((reply-length (with-input-from-string (socket-receive ipc 4) (cut read-u32)))
	  (reply-type (with-input-from-string (socket-receive ipc 4) (cut read-u32))))
      (read-json (socket-receive ipc reply-length)))))
;;    (socket-close ipc)))