Tony, You probably want to look at make-eval-factory and make-base-eval-factory. They are in scribble/eval rather than racket/sandbox, I think mostly as a quirk of history.
Carl Eastlund On Thu, Oct 27, 2011 at 7:32 PM, Tony Garnock-Jones <to...@ccs.neu.edu> wrote: > I've managed to kludge together a solution that seems to do what I want. > It seems that it's a shared *namespace* instance I want, with a fresh > evaluator for each connection, and the only (?) control over namespaces > for sandboxes is via sandbox-namespace-specs. It isn't the most elegant, > but here's the code: > > ;;--- > #lang racket/base > > (require racket/tcp) > (require racket/sandbox) > > (define e (make-base-namespace)) > > (define (shell in out) > (printf "Accepted\n") > (fprintf out "Hello.\n") > (parameterize ((current-input-port in) > (current-output-port out) > (current-error-port out) > (sandbox-input in) > (sandbox-output out) > (sandbox-error-output out) > (current-namespace e) > (sandbox-namespace-specs (list (lambda () e)))) > (parameterize ((current-eval (make-evaluator '(begin)))) > (read-eval-print-loop)) > (fprintf out "\nGoodbye!\n") > (close-input-port in) > (close-output-port out))) > > (define s (tcp-listen 2322 4 #t)) > (printf "Accepting...\n") > (let loop () > (define-values (i o) (tcp-accept s)) > (thread (lambda () > (shell i o))) > (loop)) > ;;--- > > Any suggestions people have for improving that are very welcome. > > Regards, > Tony > > On 2011-10-27 3:45 PM, Tony Garnock-Jones wrote: >> Hi all, >> >> The example TCP-listening sandboxed REPLs given nearish the top of >> http://docs.racket-lang.org/reference/Sandboxed_Evaluation.html differ >> slightly: the one that only works from the toplevel shares a namespace >> and evaluator between all the connections, but the one that works from a >> module uses a fresh namespace and evaluator for each connection. >> >> How can I set things up so that >> >> - a single "global environment" is shared between all connections, but >> - each connection gets its own input and output ports, connected >> to the socket? >> >> I'd like to be able to connect in one terminal, say "(define x 123)", >> then connect in another terminal and have "x" result in "123". I'd also >> like "(display 'hello)" to print to the issuing terminal rather than >> going only to one or the other. >> >> Does this sound like a familiar problem? Have others solved this before? >> I feel like I'm missing something about the distinction between >> namespaces and evaluators... >> >> Regards, >> Tony _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
