*rpc-port*

The value of this variable identifies the default RPC port in the dynamic environment.

The variable is bound explicitly by the macro with-remote-port.

When an in-bound remote call is evaluated, the dynamic environment binds this variable to the port which received the call.

In user programs, it is unwise to bind or assign a value to this variable, whether by let-binding, lambda-binding, or using setf or setq.

An out-bound remote call is identified as a callback when the destination port is eq to the default port, and the default port has not been re-bound to some other port in the dynamic environment.

(defun remotely-called-function ()
    (let ((in-port *rpc-port*))
      (rcall 'foo)  ;; this is a callback
      (with-remote-port (in-port) 
            (rcall 'bar)  ;; this is a callback
            )
      (with-remote-port (other-port)
            (with-remote-port (in-port) 
               (rcall 'bar)  ;; this is NOT a callback
               )
            )
      (rcall 'bar)  ;; this is a callback
      ))

See also rpc.htm for general information on the Remote Procedure Call utility in Allegro CL.

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This page was not revised from the 10.0 page.
Created 2019.8.20.