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Diffstat (limited to 'tests/gui/concurrentreadandprint.rkt')
-rw-r--r-- | tests/gui/concurrentreadandprint.rkt | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/tests/gui/concurrentreadandprint.rkt b/tests/gui/concurrentreadandprint.rkt new file mode 100644 index 0000000..95d02c1 --- /dev/null +++ b/tests/gui/concurrentreadandprint.rkt @@ -0,0 +1,75 @@ +#lang racket +(require math/base) ;; for random number generation + +;; a proof of concept +;; one thread waits for input +;; another displays messages in the background + + +;; create custodian for managing all resources +;; so we can shutdown everything at once +;(define guard (make-custodian (current-custodian))) +;(current-custodian guard) +;; reads values continously from stdin and redisplays them +(define (read-loop) + (display (read-line)) + (display "\n") + (read-loop) + ) + +(define input-prompt "input: ") +(define output-prompt "output: ") + +;; prompt for username and bind to a variable username +(display "What's your name?\n") +(define username (read-line)) +(define usernamei (string-append username ": ")) ;; make username appear nicer in a prompt +(define fair (make-semaphore 1)) + +;; intelligent read, quits when user types in "quit" +(define (read-loop-i) + + + ;(semaphore-wait fair) + (display usernamei) + (define input (read-line)) + ;; do something over here with input maybe send it out + + ;; Tests input if its a quit then kills all threads + ;; An if would be better here tbh + (cond ((string=? input "quit") (begin (kill-thread a) + (kill-thread t)))) + (display (string-append output-prompt input "\n")) + ;(semaphore-post fair) + (read-loop-i) + ) + + +;; print hello world continously +;; "(hello-world)" can be executed as part of background thread +;; that prints in the event there is something in the input port +(define (hello-world) + (sleep (random-integer 0 15)) ;; sleep between 0 and 15 seconds to simulate coms + ;; with server + ;(semaphore-wait fair) + ;; we will retrieve the line printed below from the server + ;; at this time we simulate the input from different users + (define what-to-print (random-integer 0 2)) + (if (= what-to-print 0) + (display "Doug: What's up, up?\n") + (display "Fred: Looking good, good!\n")) + ;(semaphore-post fair) + (hello-world)) + +(define t (thread (lambda () + (read-loop-i)))) +(define a (thread (lambda () + (hello-world)))) + +(thread-wait t) ;; returns prompt back to drracket +;; below doesn't execute +; (sleep 10) +; (kill-thread t) +; (define a (thread (display "hello world!\n"))) +; (display "John: hello soso\n") +; (display "Emmanuel: cumbaya!!!!\n") |