- Gambit-list - mailman.iro.umontreal.ca

ffi and u8vectors, s8vectors, ...
by Andreas Huber 03 Jui '07

03 Jui '07

Hi, I've been playing around with Gambit's foreign function interface today, and the big stumbling block i've hit is that I cannot easily pass u8vectors to native code, i.e. u8vector is not compatible with (pointer void) or (pointer unsigned-int8). Is there a chance this might be changed in the future? I would _not_ want the address of a copy of the bytevector's contents to be passed to c-code but a pointer to the original u8vector's storage location instead. I am guaranteed that GC will not move my memory for the duration of this foreign call, am I not? (unless of course, scheme is reentered from within that native call, in which case all bets are off, right?) If there's an easier way of accomplishing this already supported I would of course love to hear it. Best regards, Andreas

2 2

Bill Clementson's Blog: Parallel Map Beer Song in Erlang
by Bradley Lucier 02 Jui '07

02 Jui '07

How does one do parmap, found in the following blog entry by Bill Clementson, in Termite? http://bc.tech.coop/blog/070601.html It appears a similar implementation would use list comprehensions; so a related question is whether anyone is interesting in snowing srfi-42: http://srfi.schemers.org/srfi-42/srfi-42.html Brad PS: I hereby claim the first use of "to show" as a transitive verb in English!

2 2

Flushing not done ?
by Adrien Pierard 01 Jui '07

01 Jui '07

Hello ! I've been writing some code today, dumping data in files on the hard disk. I knew that gambit, and many (if not all) languages buffers data before enventually writing it to the disk. What puzzled me today, is that it actually never got written ! Here is the code : (let ((o (open-output-file "/tmp/flushed-data"))) (display "whirl" o) (display "\n" o)) I thought that when the gambit process cleanly finishes, it would flush the port, though it didn't. I had to append a (close-output-port o) in order to have my data dumped. So, is that an undocumented feature, do I have to do the display in the IO monad ? Or is it just fully compliant with the "do what you want with the little constraint in the RnRS" ? This behaviours happens as well with interpreted code as woth compiled code. Isn't the OS (or the libc behind gambit) supposed to flush when the process terminates ? Should I stick to CALL-WITH-OUPUT-FILE or always close ports ? Adrien -- " am not a Church numeral; I am a free variable!" (The Scheme Underground)

3 2

compile-file + 0 args c-lambda + syntax-case
by Phil Dawes 31 Mai '07

31 Mai '07

Hi Marc, Hi gambit people, I'm not sure how fixable this is, but if I try to use 'compile-file' to compile a file containing a c-lambda that has no arguments, from an environment with syntax-case loaded then I get the following error: *** ERROR IN map -- invalid syntax () If the c-lambda has arguments then it works. If syntax-case isn't loaded then it works also. E.g. ------ c.scm ----- (define get-value (c-lambda () (int32) "___result = 35;")) ------------------- $ gsc - > (compile-file "c") #t > (load "~~/syntax-case.scm") "/usr/local/Gambit-C/4.0b22/syntax-case.scm" > (compile-file "c") *** ERROR IN map -- invalid syntax () This is in gambit-4.0b22 on x86 linux BTW. Also, while I'm here, is there a better way to reveal the value of things to scheme from C? In particular I want to be able to get a pointer to a C function so that it can be passed to bsearch. Many thanks, Phil

1 0

Comparing gambit bignums with gmp 4.2.1
by Bradley Lucier 31 Mai '07

31 Mai '07

I'll get these comparisons out now before gmp 5 comes out ;-). Here are some comparisons with gmp for large integers. This is with the _num.scm I sent you earlier. (define a (time (expt 3 2095903))) (define b (time (expt 7 1183294))) (define c (time (expt 11 1920505))) I chose these numbers because they were used in a talk by Paul Zimmermann; I presume he chose them because > (map integer-length (list a b c (expt 10 1000000))) (3321928 3321927 6643856 3321929) I believe that on smaller numbers gmp should be significantly faster than gambit. On my laptop (1.67GHz PowerPC 7450, gcc 4.1.2, 32 bit), times in seconds Gambit GMP 4.2.1 (* a b) .907 .40 (quotient c a) 4.176 1.70 (integer-sqrt c) 4.179 1.35 (gcd a b) 55.494 224.31 On my desktop (2.0GHz PowerPC 970, gcc 4.1.2, 64 bit): (* a b) .352 .13 (quotient c a) 1.744 .59 (integer-sqrt c) 1.813 .46 (gcd a b) 24.071 36.56 On a server (2.2GHz Opteron, gcc 4.1.2, 64 bit): (* a b) .344 .17 (quotient c a) 1.550 .73 (integer-sqrt c) 1.526 .57 (gcd a b) 17.713 31.34 GMP was compiled with gcc -O3 -mcpu=970 -m64 -o test test.c -I/pkgs/gmp-4.2.1-64/include/ - L/pkgs/gmp-4.2.1-64/lib -lgmp and similarly for the other machines. Brad

1 1

Re: [gambit-list] problem compiling gambit
by Gabriel Filion 30 Mai '07

30 Mai '07

Great! it worked well. thank you :) David St-Hilaire wrote: > Hi Gabriel! > > I had the same problem the other day. After looking into the problem > with Marc, he came to the conclusion that the thing to do is to add some > ___BEGIN_C_LINKAGE and ___END_C_LINKAGE at the problematic position in > lib/os.h, so you'd get something like: > > #ifdef USE_environ > ___BEGIN_C_LINKAGE > extern char **environ; > ___END_C_LINKAGE > #endif > > I hope this will resolve your problem! > > David > -- Gabriel Filion

1 0

problem compiling gambit
by Gabriel Filion 29 Mai '07

29 Mai '07

Hello, I have a problem compiling gambit, it says a definition in unistd.h redefines something. gabster@barbiche:~/local/gambc-4.0b22$ ./configure --prefix=/home/gabster/local/gambit/ --enable-single-host --enable-cplusplus [ ... ] gabster@barbiche:~/local/gambc-4.0b22$ make making all in include make[1]: Entering directory `/home/gabster/local/gambc-4.0b22/include' make[1]: Leaving directory `/home/gabster/local/gambc-4.0b22/include' making all in lib make[1]: Entering directory `/home/gabster/local/gambc-4.0b22/lib' g++ -I../include -I. -Wall -W -Wno-unused -O1 -fno-math-errno -fschedule-insns2 -fno-trapping-math -fno-strict-aliasing -fwrapv -fexpensive-optimizations -fforce-addr -fpeephole2 -falign-jumps -falign-functions -fno-function-cse -ftree-copyrename -ftree-fre -ftree-dce -fregmove -fgcse-las -freorder-functions -fcaller-saves -fno-if-conversion2 -foptimize-sibling-calls -fcse-skip-blocks -funit-at-a-time -finline-functions -fomit-frame-pointer -fPIC -fno-common -mieee-fp -DHAVE_CONFIG_H -D___PRIMAL -D___LIBRARY -D___GAMBCDIR=\"/home/gabster/local/gambit//4.0b22\" -c _io.c g++ -I../include -I. -Wall -W -Wno-unused -O1 -fno-math-errno -fschedule-insns2 -fno-trapping-math -fno-strict-aliasing -fwrapv -fexpensive-optimizations -fforce-addr -fpeephole2 -falign-jumps -falign-functions -fno-function-cse -ftree-copyrename -ftree-fre -ftree-dce -fregmove -fgcse-las -freorder-functions -fcaller-saves -fno-if-conversion2 -foptimize-sibling-calls -fcse-skip-blocks -funit-at-a-time -finline-functions -fomit-frame-pointer -fPIC -fno-common -mieee-fp -DHAVE_CONFIG_H -D___PRIMAL -D___LIBRARY -D___GAMBCDIR=\"/home/gabster/local/gambit//4.0b22\" -c _num.c g++ -I../include -I. -Wall -W -Wno-unused -O1 -fno-math-errno -fschedule-insns2 -fno-trapping-math -fno-strict-aliasing -fwrapv -fexpensive-optimizations -fforce-addr -fpeephole2 -falign-jumps -falign-functions -fno-function-cse -ftree-copyrename -ftree-fre -ftree-dce -fregmove -fgcse-las -freorder-functions -fcaller-saves -fno-if-conversion2 -foptimize-sibling-calls -fcse-skip-blocks -funit-at-a-time -finline-functions -fomit-frame-pointer -fPIC -fno-common -mieee-fp -DHAVE_CONFIG_H -D___PRIMAL -D___LIBRARY -D___GAMBCDIR=\"/home/gabster/local/gambit//4.0b22\" -c _std.c os.h:537: error: previous declaration of ‘char** environ’ with ‘C++’ linkage /usr/include/unistd.h:500: error: conflicts with new declaration with ‘C’ linkage make[1]: *** [_std.o] Error 1 make[1]: Leaving directory `/home/gabster/local/gambc-4.0b22/lib' make: *** [all-recursive] Error 1 am I missing some library or anything else? I just reinstalled my computer and before doing so, I was able to compile gambit-4.0b22 with the same options to configure without a problem. -- Gabriel Filion

1 0

how to exec shell command then collect result as a string? (like with perl $a=`ls`; )
by Naruto Canada 28 Mai '07

28 Mai '07

hi how to exec shell command then collect result as a string? (like with perl $a=`ls`;) I need to call maple and collect the result. shell-command seems to return only exit status. Thanks Ask a question on any topic and get answers from real people. Go to Yahoo! Answers and share what you know at http://ca.answers.yahoo.com

4 3

Revision control systems Scheme interface
by Guillaume Cartier 26 Mai '07

26 Mai '07

The post by Christian where he talked about doing a Scheme interface to GIT has made me realize how useful a scheme interface to a good revision control system would be in my projects. If enough people feel the same way, maybe we could start a small project and build one. It should not be a lot of work. Anyone knows about any Scheme interface in existence that could give us a head start? Also, it should not be too hard to support many revision control systems by building the interface in a generic fashion that would delegate to specific interfaces. Guillaume

4 5

Re: [gambit-list] Mercurial
by Marc Feeley 26 Mai '07

26 Mai '07

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 25-May-07, at 8:52 AM, Aycan iRiCAN wrote: > Marc Feeley wrote: >> I have pretty much settled on Mercurial (http://www.selenic.com/ >> mercurial/wiki/) as the source control management system for Gambit. >> If you have another suggestion then please let me know ASAP. > I suggest Darcs. It's distributed, interactive and supports > spontaneous > branches. It supports various platforms including Windows, Mac OS X, > FreeBSD, NetBSD, Solaris, AIX, Linux and Cygwin. It's reliable, we're > using darcs around a year (constantly developing applications > everyday) > and had no problem. > > http://darcs.net/DarcsWiki > > Best Regards. I was considering darcs but the "conflict bug" seems serious: http://programming.reddit.com/info/19vvs/comments Marc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (Darwin) iD8DBQFGVuB+//V9Zc2T/v4RAnSPAKCNbv2IM42ui2gpZy9MIVpAuQtT/wCcCyxT TPfN2wJXpAymTwW08qVACno= =IJ5S -----END PGP SIGNATURE-----

3 2