[Gcl-devel] Re: Seg fault in write-string.11

[Sam Steingold]

> * Camm Maguire <address@hidden> [2004-02-23 11:34:42 -0500]:
>
> What is happening here is that you are creating a stream loop, as
> *standard-input* in GCL eval's to a synonym stream to *terminal-io*.

in CLISP *standard-input* also evaluates to
#<IO SYNONYM-STREAM *TERMINAL-IO*>
nevertheless the test apparently passes:

   (with-output-to-string (os)
     (let ((*terminal-io* (make-two-way-stream *standard-input* os)))
       (write-string "951" t)
       (close *terminal-io*)))
==> "951"

I see no problem with the code as long as you do not try to read from
*TERMINAL-IO* bound to that TWO-WAY-STREAM (which will cause a loop in
both CLISP and GCL).

> I was wondering whether this was a proper initial value for
> *standard-input* and checked the spec -- apparently this arrangement
> is specifically allowed.

indeed.

> The code below overruns the C stack as it
> endlessly recurses trying to close *terminal-io*.

closing a TWO-WAY-STREAM should not recurse.


-- 
Sam Steingold (http://www.podval.org/~sds) running w2k
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