strings draft Tom Lord (22 Jan 2004 04:58 UTC)
Re: strings draft Shiro Kawai (22 Jan 2004 09:46 UTC)
Re: strings draft Tom Lord (22 Jan 2004 17:32 UTC)
Re: strings draft Shiro Kawai (23 Jan 2004 05:03 UTC)
Re: strings draft Tom Lord (24 Jan 2004 00:31 UTC)
Re: strings draft Matthew Dempsky (24 Jan 2004 03:00 UTC)
Re: strings draft Shiro Kawai (24 Jan 2004 03:27 UTC)
Re: strings draft Tom Lord (24 Jan 2004 04:18 UTC)
Re: strings draft Shiro Kawai (24 Jan 2004 04:49 UTC)
Re: strings draft Tom Lord (24 Jan 2004 18:47 UTC)
Re: strings draft Shiro Kawai (24 Jan 2004 22:16 UTC)
Octet vs Char (Re: strings draft) Shiro Kawai (26 Jan 2004 09:58 UTC)
Strings, one last detail. bear (30 Jan 2004 21:12 UTC)
Re: Strings, one last detail. Shiro Kawai (30 Jan 2004 21:43 UTC)
Re: Strings, one last detail. Tom Lord (31 Jan 2004 00:13 UTC)
Re: Strings, one last detail. bear (31 Jan 2004 20:26 UTC)
Re: Strings, one last detail. Tom Lord (31 Jan 2004 20:42 UTC)
Re: Strings, one last detail. bear (01 Feb 2004 02:29 UTC)
Re: Strings, one last detail. Tom Lord (01 Feb 2004 02:44 UTC)
Re: Strings, one last detail. bear (01 Feb 2004 07:53 UTC)
Re: Octet vs Char (Re: strings draft) bear (26 Jan 2004 19:04 UTC)
Re: Octet vs Char (Re: strings draft) Matthew Dempsky (26 Jan 2004 20:12 UTC)
Re: Octet vs Char (Re: strings draft) Matthew Dempsky (26 Jan 2004 20:40 UTC)
Re: Octet vs Char Shiro Kawai (26 Jan 2004 23:39 UTC)
Re: Octet vs Char (Re: strings draft) Ken Dickey (27 Jan 2004 04:33 UTC)
Re: Octet vs Char Shiro Kawai (27 Jan 2004 05:12 UTC)
Re: Octet vs Char Tom Lord (27 Jan 2004 05:23 UTC)
Re: Octet vs Char bear (27 Jan 2004 08:35 UTC)
Re: Octet vs Char (Re: strings draft) bear (27 Jan 2004 08:33 UTC)
Re: Octet vs Char (Re: strings draft) Ken Dickey (27 Jan 2004 15:43 UTC)
Re: Octet vs Char (Re: strings draft) bear (27 Jan 2004 19:06 UTC)
Re: strings draft bear (22 Jan 2004 19:05 UTC)
Re: strings draft Tom Lord (23 Jan 2004 01:53 UTC)
READ-OCTET (Re: strings draft) Shiro Kawai (23 Jan 2004 06:01 UTC)
Re: strings draft bear (23 Jan 2004 07:04 UTC)
Re: strings draft bear (23 Jan 2004 07:20 UTC)
Re: strings draft Tom Lord (24 Jan 2004 00:02 UTC)
Re: strings draft Alex Shinn (26 Jan 2004 01:59 UTC)
Re: strings draft Tom Lord (26 Jan 2004 02:22 UTC)
Re: strings draft bear (26 Jan 2004 02:35 UTC)
Re: strings draft Tom Lord (26 Jan 2004 02:48 UTC)
Re: strings draft Alex Shinn (26 Jan 2004 03:00 UTC)
Re: strings draft Tom Lord (26 Jan 2004 03:14 UTC)
Re: strings draft Shiro Kawai (26 Jan 2004 04:57 UTC)
Re: strings draft Alex Shinn (26 Jan 2004 04:58 UTC)
Re: strings draft tb@xxxxxx (23 Jan 2004 18:48 UTC)
Re: strings draft bear (24 Jan 2004 02:21 UTC)
Re: strings draft tb@xxxxxx (23 Jan 2004 02:10 UTC)
Re: strings draft Tom Lord (23 Jan 2004 02:29 UTC)
Re: strings draft tb@xxxxxx (23 Jan 2004 02:44 UTC)
Re: strings draft Tom Lord (23 Jan 2004 02:53 UTC)
Re: strings draft tb@xxxxxx (23 Jan 2004 03:04 UTC)
Re: strings draft Tom Lord (23 Jan 2004 03:16 UTC)
Re: strings draft tb@xxxxxx (23 Jan 2004 03:42 UTC)
Re: strings draft Alex Shinn (23 Jan 2004 02:35 UTC)
Re: strings draft tb@xxxxxx (23 Jan 2004 02:42 UTC)
Re: strings draft Tom Lord (23 Jan 2004 02:49 UTC)
Re: strings draft Alex Shinn (23 Jan 2004 02:58 UTC)
Re: strings draft tb@xxxxxx (23 Jan 2004 03:13 UTC)
Re: strings draft Alex Shinn (23 Jan 2004 03:19 UTC)
Re: strings draft Bradd W. Szonye (23 Jan 2004 19:31 UTC)
Re: strings draft Alex Shinn (26 Jan 2004 02:22 UTC)
Re: strings draft Bradd W. Szonye (06 Feb 2004 23:30 UTC)
Re: strings draft Bradd W. Szonye (06 Feb 2004 23:33 UTC)
Re: strings draft Alex Shinn (09 Feb 2004 01:45 UTC)
specifying source encoding (Re: strings draft) Shiro Kawai (09 Feb 2004 02:51 UTC)
Re: strings draft Bradd W. Szonye (09 Feb 2004 03:39 UTC)
Re: strings draft tb@xxxxxx (23 Jan 2004 03:12 UTC)
Re: strings draft Alex Shinn (23 Jan 2004 03:28 UTC)
Re: strings draft tb@xxxxxx (23 Jan 2004 03:44 UTC)
Parsing Scheme [was Re: strings draft] Ken Dickey (23 Jan 2004 17:02 UTC)
Re: Parsing Scheme [was Re: strings draft] bear (23 Jan 2004 17:56 UTC)
Re: Parsing Scheme [was Re: strings draft] tb@xxxxxx (23 Jan 2004 18:50 UTC)
Re: Parsing Scheme [was Re: strings draft] Per Bothner (23 Jan 2004 18:56 UTC)
Re: Parsing Scheme [was Re: strings draft] Tom Lord (23 Jan 2004 20:26 UTC)
Re: Parsing Scheme [was Re: strings draft] Per Bothner (23 Jan 2004 20:57 UTC)
Re: Parsing Scheme [was Re: strings draft] Tom Lord (23 Jan 2004 21:44 UTC)
Re: Parsing Scheme [was Re: strings draft] Ken Dickey (23 Jan 2004 21:47 UTC)
Re: Parsing Scheme [was Re: strings draft] Tom Lord (23 Jan 2004 23:22 UTC)
Re: Parsing Scheme [was Re: strings draft] Ken Dickey (25 Jan 2004 01:03 UTC)
Re: Parsing Scheme [was Re: strings draft] Tom Lord (25 Jan 2004 03:01 UTC)
Re: Parsing Scheme [was Re: strings draft] Tom Lord (23 Jan 2004 20:07 UTC)
Re: Parsing Scheme [was Re: strings draft] tb@xxxxxx (23 Jan 2004 21:22 UTC)
Re: Parsing Scheme [was Re: strings draft] Tom Lord (23 Jan 2004 22:38 UTC)
Re: Parsing Scheme [was Re: strings draft] tb@xxxxxx (24 Jan 2004 06:48 UTC)
Re: Parsing Scheme [was Re: strings draft] Tom Lord (24 Jan 2004 18:41 UTC)
Re: Parsing Scheme [was Re: strings draft] tb@xxxxxx (24 Jan 2004 19:34 UTC)
Re: Parsing Scheme [was Re: strings draft] Tom Lord (24 Jan 2004 21:48 UTC)
Re: strings draft Matthew Dempsky (25 Jan 2004 06:59 UTC)
Re: strings draft Tom Lord (25 Jan 2004 07:16 UTC)
Re: strings draft Matthew Dempsky (26 Jan 2004 23:52 UTC)
Re: strings draft Tom Lord (27 Jan 2004 00:30 UTC)

Strings, one last detail. bear 30 Jan 2004 21:12 UTC

Okay, I'm still looking at this "portable" FFI and there's one crucial
thing missing to make it portable, in terms of strings.

I can treat SCHEME_EXTRACT_STRING as a request to make a copy of a
string in a format acceptable to C code in some buffer, register it as
"floating garbage" with the GC, return a pointer to that buffer, and
lock the garbage collector until the scheme runtime is reentered.  If
the C code just wants to _read_ what's there, that's necessary and
sufficient.  But a developer looking at the specification of
SCHEME_EXTRACT_STRING ("a pointer to the storage occupied by the
characters of the string") may expect to be able to _write_ the
contents of the buffer and have the changes written show up in the
string on the scheme side, and code relying on that will be a problem.

I see another routine, SCHEME_ENTER_STRING, that is clearly the correct
way to assign a changed string value to a scheme string variable from C
code.

What's missing is an explicit declaration that it is unspecified
whether or not values written into the buffer pointed at by the result
of SCHEME_EXTRACT_STRING mutate the scheme string that was originally
referred to,

You come close to saying this when you mention that the pointer may
only be valid until the next GC, but reading it out of that statement
takes a basic understanding of copying GC's and more thought about
their interaction with the runtime than I think a lot of people will
expend.

				Bear