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Hmm. Let's see. I can test on the following platforms:<br>
<br>
OSX<br>
Linux (slackware 8, suse 10)<br>
Windows XP<br>
<br>
FreeBSD --> I can make a vmware image.<br>
<br>
Solaris: I can't test that.<br>
AIX 5.3: I could test that.<br>
<br>
Most platforms support pthreads though.<br>
<br>
Note however the code in the 'gc' subdir:<br>
<br>
<pre># include "gc_config_macros.h"
# include "private/gcconfig.h"
# include <stdio.h>
int main()
{
# if defined(GC_USE_LD_WRAP)
printf("-Wl,--wrap -Wl,dlopen "
"-Wl,--wrap -Wl,pthread_create -Wl,--wrap -Wl,pthread_join "
"-Wl,--wrap -Wl,pthread_detach "
"-Wl,--wrap -Wl,pthread_sigmask -Wl,--wrap -Wl,sleep\n");
# endif
# if defined(GC_LINUX_THREADS) || defined(GC_IRIX_THREADS) \
|| defined(GC_SOLARIS_PTHREADS) \
|| defined(GC_DARWIN_THREADS) || defined(GC_AIX_THREADS)
printf("-lpthread\n");
# endif
# if defined(GC_FREEBSD_THREADS)
# if (__FREEBSD_version >= 500000)
printf("-lpthread\n");
# else
printf("-pthread\n");
# endif
# endif
# if defined(GC_NETBSD_THREADS)
printf("-lpthread -lrt\n");
# endif
# if defined(GC_HPUX_THREADS) || defined(GC_OSF1_THREADS)
printf("-lpthread -lrt\n");
# endif
# if defined(GC_SOLARIS_THREADS) && !defined(GC_SOLARIS_PTHREADS)
printf("-lthread -ldl\n");
# endif
# if defined(GC_WIN32_THREADS) && defined(CYGWIN32)
printf("-lpthread\n");
# endif
# if defined(GC_OSF1_THREADS)
printf("-pthread -lrt"); /* DOB: must be -pthread, not -lpthread */
# endif
/* You need GCC 3.0.3 to build this one! */
/* DG/UX native gcc doesnt know what "-pthread" is */
# if defined(GC_DGUX386_THREADS)
printf("-ldl -pthread\n");
# endif
return 0;
}
</pre>
It all seems to be pthreads, except for standard windows of course.<br>
<br>
Best wishes,<br>
<br>
hans<br>
<br>
<br>
<br>
Eli Barzilay schreef:
<blockquote cite="mid:18077.12122.360482.65738@kinyarwanda.ccs.neu.edu"
type="cite">
<pre wrap="">On Jul 17, Hans Oesterholt-Dijkema wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Dear Eli,
Thanks for your elaborate reply. I must admit that you are right on
a lot of points. There's one advantage of having the "non blocking"
ffi call, and that is: one keeps access to the returned C results,
without having to serialize the results over a pipe.
</pre>
</blockquote>
<pre wrap=""><!---->
Yes, but that's not a big problem. Instead of some
(define foo (non-blocking-call ....)) ; returns a foo pointer
(printf "foo->bar = ~s\n" (foo-bar foo))
(printf "foo->blah = ~s\n" (foo-blah foo))
you can do this:
(define foo (gensym))
(send-subprocess `(define ,foo (blocking-call ...)))
(printf "foo->bar = ~s\n" (send-subprocess `(foo-bar ,foo)))
(printf "foo->blah = ~s\n" (send-subprocess `(foo-blah ,foo)))
(And a few macros can make it even more transparent...)
This is equivalent to the foreign machinery that pulls off values from
a C object.
</pre>
</blockquote>
<br>
<blockquote cite="mid:18077.12122.360482.65738@kinyarwanda.ccs.neu.edu"
type="cite">
<pre wrap=""></pre>
<blockquote type="cite">
<pre wrap="">That said. The current mzscheme source distribution depends already
on threads afaik (have a look in the gc subdir?).
</pre>
</blockquote>
<pre wrap=""><!---->
But it does assume that Scheme execution is done on a single thread.
For example, using Scheme callbacks will probably break things if done
on a different thread. But this is obviously a problem either way,
subprocess, fork, or whatever. (And, for example, being able to
serialize closures would be a solution in all of cases.)
In any case, let me clarify: I do believe that async calls *are*
useful. If you can verify that the c-threads code that you wrote
works fine on Windows, OSX, Linux, BSD, and Solaris then it would be a
good starting point to integrate that in. (If you don't have access
to these platforms, then perhaps you can write enough test cases and I
can run them.) Yes, callbacks from a thread would break things -- but
the reason for the `(unsafe!)' statement is that you can break things
anyway, so it's probably fine to throw that on the programmer's
shoulders.
</pre>
</blockquote>
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