[plt-scheme] TCP example not working

From: Eli Barzilay (eli at barzilay.org)
Date: Fri Oct 10 05:57:25 EDT 2008

On Oct 10, Veer wrote:
> The example below is given in the guide hangs around  (read-line s-in) .
> (define server (tcp-listen 12345))
> (define-values (c-in c-out) (tcp-connect "localhost" 12345))
> (define-values (s-in s-out) (tcp-accept server))
> (display "hello\n" c-out)
> (read-line s-in)
> (close-output-port c-out)
> (read-line s-in)

You're right -- the problem is that nothing actually goes out on the
connection because it is buffered.  One way to make it work is to add

  (flush-output c-out)

after the `display' line, and another is to move

   (close-output-port c-out)

one line up to before the `read-line' (because closing the port also
flushes it).

I committed the last change to the guide.

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                  http://www.barzilay.org/                 Maze is Life!

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