ikarus/lab/tcp-connect-nonblocking-exa...

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1.0 KiB
Scheme
Executable File

#!/usr/bin/env scheme-script
(import (ikarus))
;;; very simple demo for how to connect to a server,
;;; send a request and receive a response.
;;; Here, we use an asynchronous IO socket. We wrap the whole
;;; operation with an exception handler to handle the would-block
;;; conditions. If we do get a would-block condition, we just
;;; return, causing the read/write operation to be restarted until
;;; it succeeds. Pretty lame at this point, but it works.
(define (http-cat host)
(with-exception-handler
(lambda (c)
;;; just return and let it retry until it succeeds
(unless (i/o-would-block-condition? c)
(raise c)))
(lambda ()
(let-values ([(op ip) (tcp-connect-nonblocking host "http")])
(let ([op (transcoded-port op (native-transcoder))]
[ip (transcoded-port ip (native-transcoder))])
(display "GET /\n" op)
(display (get-string-all ip))
(close-input-port ip)
(close-output-port op))))))
(http-cat "www.google.com")
(newline)
;(http-cat "127.0.0.1")