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(module
nmsg-transport
(
nmsg:start-server
nmsg:open-send-close
nmsg:open-send-receive
)
(import scheme posix chicken data-structures ports)
(use pkts)
;; (contacts (alist-ref 'contact attrib))
(set! res (if (equal? resp "ok")
#t
#f))))
"recv thread"))
(th2 (make-thread (lambda ()
(thread-sleep! timeout)
(thread-terminate! th1))
"timer thread")))
(thread-start! th1)
(thread-start! th2)
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(module
nmsg-transport
(
nmsg:start-server
nmsg:open-send-close
nmsg:open-send-receive
nmsg:close
)
(import scheme posix chicken data-structures ports)
(use nanomsg srfi-18)
;;start a server, returns the connection
;;
(define (nmsg:start-server portnum )
(let ((rep (nn-socket 'rep)))
(handle-exceptions
exn
(let ((emsg ((condition-property-accessor 'exn 'message) exn)))
(print "ERROR: Failed to start server \"" emsg "\"")
#f)
(nn-bind rep (conc "tcp://*:" portnum)))
rep))
;; open connection to server, send message, close connection
;;
;; to take an action on failure use proc which is called with the error info
;; (proc exn errormsg)
;;
;; returns the response or #f if no response within timeout
;;
(define (nmsg:open-send-close host-port msg attrib #!key (timeout 3)(proc #f)) ;; default timeout is 3 seconds
(let ((req (nn-socket 'req))
(uri (conc "tcp://" host-port))
(res #f)
(mode (alist-ref 'mode attrib)))
(handle-exceptions
exn
(let ((emsg ((condition-property-accessor 'exn 'message) exn)))
;; Send notification
(if proc (proc exn emsg))
#f)
(nn-connect req uri)
(print "Connected to the server " )
(nn-send req msg)
(print "Request Sent")
(let* ((th1 (make-thread (lambda ()
(let ((resp (nn-recv req)))
(nn-close req)
(set! res resp)))
"recv thread"))
(th2 (make-thread (lambda ()
(thread-sleep! timeout)
(thread-terminate! th1))
"timer thread")))
(thread-start! th1)
(thread-start! th2)
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(thread-terminate! th1))
"timer thread")))
(thread-start! th1)
(thread-start! th2)
(thread-join! th1)
res))))
;; get a signature for identifing this process
(define (nmsg:get-process-signature)
(conc (get-host-name) " " (current-process-id)))
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(thread-terminate! th1))
"timer thread")))
(thread-start! th1)
(thread-start! th2)
(thread-join! th1)
res))))
(define (nmsg:close conn)
(nn-close conn))
)
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