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From: Pascal J. Bourguignon on 16 Jul 2010 17:12
pjb(a)informatimago.com (Pascal J. Bourguignon) writes:

> "ansofive(a)gmail.com" <ansofive(a)gmail.com> writes:
>
>> Hi,
>>
>> I've been playing around with this and I've discovered that listen
>> seems to only work with character streams. I've only tried it on
>> clisp at this point but it wouldn't suprise me if it was the same on
>> sbcl. The HyperSpec says "Returns true if there is a character
>> immediately available ... listen is intended to be used when input-
>> stream obtains characters from an interactive device such as a
>> keyboard. " which seems to suggest that listen wants a character
>> stream.
>
> Oops, I forgot that.
>
>
>> Is there character encoding that allows be to read 8-bit characters?
>> Hmmmm..... Seems to me I remember something from Practical Common
>> Lisp......
>
> Yes, you can use charset:iso-8859-1 or any of the other iso-8859-* charsets.

However, you may still have difficulties, if it's a binary stream,
because clisp processes character streams, in particular CR, CR-LF and
LF sequences are converted to #\newline. I don't know a way to
disable that.

--
__Pascal Bourguignon__ http://www.informatimago.com/
From: Dennis Dunn on 17 Jul 2010 07:11
Hi Pascal,


On 7/16/2010 5:12 PM, Pascal J. Bourguignon wrote:
>> Yes, you can use charset:iso-8859-1 or any of the other iso-8859-* charsets.

Thanks for the hint, I'll try it out today.

Dennis
From: ansofive on 19 Jul 2010 20:21
Success!

In my googling I ran across the ext package in clisp - a quick review
of loop and it's working. :)

#+clisp
(defun read-packet (stream)
"Read a packet from the stream."
(let ((buffer
(loop for b = (read-byte stream)
then (ext:read-byte-no-hang stream nil :eof)
until (not b)
collect b )))
(make-array (length buffer) :element-type '(unsigned-byte
8) :initial-contents buffer)))

Thanks again.

Dennis
From: Pascal Costanza on 20 Jul 2010 03:11
On 20/07/2010 02:21, ansofive(a)gmail.com wrote:
> Success!
>
> In my googling I ran across the ext package in clisp - a quick review
> of loop and it's working. :)
>
> #+clisp
> (defun read-packet (stream)
> "Read a packet from the stream."
> (let ((buffer
> (loop for b = (read-byte stream)
> then (ext:read-byte-no-hang stream nil :eof)
> until (not b)
> collect b )))
> (make-array (length buffer) :element-type '(unsigned-byte
> 8) :initial-contents buffer)))
>
> Thanks again.

Instead of

(make-array (length bla)
:element-type '(unsigned-byte 8)
:initial-contents bla)

you can also say

(coerce bla '(vector (unsigned-byte 8)))

which has a chance to be a bit more efficient.


Pascal

--
My website: http://p-cos.net
Common Lisp Document Repository: http://cdr.eurolisp.org
Closer to MOP & ContextL: http://common-lisp.net/project/closer/
From: Pascal J. Bourguignon on 20 Jul 2010 03:21
Pascal Costanza <pc(a)p-cos.net> writes:

> On 20/07/2010 02:21, ansofive(a)gmail.com wrote:
>> Success!
>>
>> In my googling I ran across the ext package in clisp - a quick review
>> of loop and it's working. :)
>>
>> #+clisp
>> (defun read-packet (stream)
>> "Read a packet from the stream."
>> (let ((buffer
>> (loop for b = (read-byte stream)
>> then (ext:read-byte-no-hang stream nil :eof)
>> until (not b)
>> collect b )))
>> (make-array (length buffer) :element-type '(unsigned-byte
>> 8) :initial-contents buffer)))
>>
>> Thanks again.
>
> Instead of
>
> (make-array (length bla)
> :element-type '(unsigned-byte 8)
> :initial-contents bla)
>
> you can also say
>
> (coerce bla '(vector (unsigned-byte 8)))
>
> which has a chance to be a bit more efficient.

It would be a sad implementation, if it made any difference.

--
__Pascal Bourguignon__ http://www.informatimago.com/
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