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Re: [Boost-users] Serialization and null pointers
by boost＠iyates.com 07 Jul '05

07 Jul '05

Robert, Thanks for all your help, I really do appreciate it. I was already serializing an stl vector, so you would think I would have thought of that! heh. Anyhow, I read through serialization/shared_ptr.hpp and sort of did the same thing on my custom shared pointer, and it is working great. I especially liked this: #define private public #include <boost/shared_ptr.hpp> #undef private hehe Thanks again! - Chris ----- Original Message ----- From: "Robert Ramey" <ramey(a)rrsd.com> To: boost-users(a)lists.boost.org Date: Wed, 6 Jul 2005 14:48:51 -0700 Subject: Re: [Boost-users] Serialization and null pointers > I suspect you didn't include <boost/serialization/shared_ptr.hpp> which > includes serialization code for shared_ptr. It also includes shared_ptr.hpp > itself. This is similar to the way the headers are organized for all the > stl collections. If you want to serialize the boost share_ptr be sure to > read about in the docs as there are a few gotchas. Also note that there the > "real soon to be released" boost 1.33 has a different shared_ptr and > different serialization of the same. > > Good Luck. > > Robert Ramey > > boost(a)iyates.com wrote: > > I was using my own home-grown one. I wrote it before I started using > > boost though. I decided to try it out with boost::shared_ptr and > > here is what I got: > > > > c:\Boost\boost_1_32_0\boost\serialization\access.hpp(106): error > > C2039: 'serialize' : is not a member of 'boost::shared_ptr<T>' > > > > > > I tried searching on boost shared_ptr serialize but came up empty. > > Any suggestions? Thanks. > > > > ----- Original Message ----- > > From: "Robert Ramey" <ramey(a)rrsd.com> > > To: boost-users(a)lists.boost.org > > Date: Tue, 5 Jul 2005 20:18:00 -0700 > > Subject: Re: [Boost-users] Serialization and null pointers > > > >> boost(a)iyates.com wrote: > >>> Thanks. If I changed the order of the members being serialized it > >>> worked fine. Weird. > >>> > >>> However, I am running into a problem. I am using reference counted > >>> Smart Pointers. If I serialize the reference counter, then when it > >>> is loaded it will likely contain too large of a reference count > >>> because there were more objects referencing the pointer when it was > >>> saved than when it was loaded. However, it works fine it just > >>> doesn't properly delete the objects because the reference count > >>> never reaches 0. > >>> > >>> If I don't serialize the reference count then the objects try to > >>> delete themselves while boost is loading them from the file. I'm > >>> guessing because of the order everything happens, the final > >>> destination isn't increasing the reference count until after boost > >>> already dereferences it. > >>> > >>> Any suggestions? > >> > >> I'm not sure which reference counted Smart Pointer you're using. If > >> you use the boost smart_ptr, its already has serializaiton done. If > >> you want to add serialization to your own Smart Pointer, you can > >> look at how it was done for the boost smart pointer - now there are > >> two versions so you have lots of ideas available. > >> > >> Robert Ramey > >> > >> > >> > >> _______________________________________________ > >> Boost-users mailing list > >> Boost-users(a)lists.boost.org > >> http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > >

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Re: [Boost-users] Serialization and null pointers
by boost＠iyates.com 06 Jul '05

06 Jul '05

I was using my own home-grown one. I wrote it before I started using boost though. I decided to try it out with boost::shared_ptr and here is what I got: c:\Boost\boost_1_32_0\boost\serialization\access.hpp(106): error C2039: 'serialize' : is not a member of 'boost::shared_ptr<T>' I tried searching on boost shared_ptr serialize but came up empty. Any suggestions? Thanks. ----- Original Message ----- From: "Robert Ramey" <ramey(a)rrsd.com> To: boost-users(a)lists.boost.org Date: Tue, 5 Jul 2005 20:18:00 -0700 Subject: Re: [Boost-users] Serialization and null pointers > boost(a)iyates.com wrote: > > Thanks. If I changed the order of the members being serialized it > > worked fine. Weird. > > > > However, I am running into a problem. I am using reference counted > > Smart Pointers. If I serialize the reference counter, then when it > > is loaded it will likely contain too large of a reference count > > because there were more objects referencing the pointer when it was > > saved than when it was loaded. However, it works fine it just doesn't > > properly delete the objects because the reference count never reaches > > 0. > > > > If I don't serialize the reference count then the objects try to > > delete themselves while boost is loading them from the file. I'm > > guessing because of the order everything happens, the final > > destination isn't increasing the reference count until after boost > > already dereferences it. > > > > Any suggestions? > > I'm not sure which reference counted Smart Pointer you're using. If you use > the boost smart_ptr, its already has serializaiton done. If you want to add > serialization to your own Smart Pointer, you can look at how it was done for > the boost smart pointer - now there are two versions so you have lots of > ideas available. > > Robert Ramey > > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > >

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mpl help
by Zeljko Vrba 06 Jul '05

06 Jul '05

-----BEGIN PGP SIGNED MESSAGE----- Hash: RIPEMD160 Hi! I would like to use mpl to generate code along the following lines (I'm trying to build a reusable library for data processing in a 'pipelined' fashion): // Arg1 and Arg2 are instances of 'stages' providing results to this // stage. F is the function taking as arguments const Arg1::result_type& // and const Arg2::result_type&. template<typename Result, typename F, typename Arg1, typename Arg2> struct stage_2 { ~ typedef Result result_type; ~ Result current_; ~ F f_; ~ Arg1 input1_; ~ Arg2 input2_; ~ stage_2(F f, Arg1 a1, Arg2 a2) : f_(f), input1_(a1), input2_(a2) { } ~ const Result &operator() { ~ current_ = f_(input1_(), input2_()); ~ return current_; ~ } }; The question: is it possible not to write manually separate stage_0, stage_1, stage_2, ... for stages taking as input results from the previous 0, 1, 2, ... stages? == Actually, what I'm trying to design: S1 -> S2 -> S3 -> .. -> Sk -> ..-> Sn ~ \_______________/ This is just a rough sketch; in the bottom line the arrow goes from S2 to Sk. Each stage (S'es in the diagram) provides input to its 'children'. This is akin to UNIX shell pipes, but more powerful in that each stage can have multiple inputs. The catch: data transformation at any stage can produce data type on output different from the one received on input. The stages should (obviously?) be parametrized by the stage result, the types of input data and the data transformation to be performed. My last resort is writing a python script to generate the boiler-plate C++ code from high-level description :) Maybe I'm on the wrong way trying to use mpl? any help is appreciated! Thanks. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (FreeBSD) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQFCyYKoFtofFpCIfhMRAzVDAJ4lMW79S4QS23ivdsLp5xEw/+G+LwCeODR7 fNweo5iwDBnvCKfUcwX3hGI= =UTnS -----END PGP SIGNATURE-----

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A newbie question about installation
by tong wang 06 Jul '05

06 Jul '05

HI: My first questio here, please be nice. I am trying to install the boost_1_31_0 on Cygwin, and get confused about which bjam should i use, I have tried boost-jam-3.1.10-1-ntx86 but get the following error: (it skipped the python libraries at the beginning, i don't need it but not sure if this matters for the following steps) ...patience... ...found 7570 targets... ...updating 3057 targets... MkDir1 C:\Boost spawn: No such file or directory Also tried the linux version : boost-jam-3.1.10-1-linuxx86 but have the following error this time. 1: Syntax error: "(" unexpected thanks a lot for any help . tong

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question of how to run quickbook
by Weining Hao 06 Jul '05

06 Jul '05

Hi all, I am a very beginner of quickbook. Now I have some questions on it. Am I in a right mailinglist? I have downloaded quickbook.zip from sourceforge.net and extracted it. 1) Shall I compile quickbook.cpp directly for getting a excutable file? I tried, but lots files included by quickbook.cpp or .hpp cannot be found. e.g boost/ref.hpp in util.hpp... Or what should I do firstly? 2) In the extracted quickbook folder, there is a readme.txt file. The content is "Hi, Place me inside your boost/tools directory. " Which file shall I put into boost/tools directory under which path? 3) Are there some more detailed guides on quickbook except things on http://spirit.sourceforge.net/dl_docs/quickbook_doc/doc/html/index.html ? Thanks in advance. Best wishs, vning ___________________________________________________________ 雅虎免费G邮箱－中国第一绝无垃圾邮件骚扰超大邮箱 http://cn.mail.yahoo.com/?id=77071

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[regex] vc71, Managed code, boost 1_32, link errors during release build
by steve lu 06 Jul '05

06 Jul '05

Hi, I am getting the following 7 link errors while making a release build of my application. (I had no problem making a debug build). //-------------------------------------------------------------------------------- RexEngine.obj : error LNK2001: unresolved external symbol "void __stdcall boost::re_detail::raise_regex_exception(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (?raise_regex_exception@re_detail@boost@@$$FYGXABV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z) RexEngine.obj : error LNK2001: unresolved external symbol "public: static class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __stdcall boost::re_detail::w32_traits_base::error_string(unsigned int)" (?error_string@w32_traits_base@re_detail@boost@@$$FSG?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@I@Z) RexEngine.obj : error LNK2001: unresolved external symbol "protected: static bool __stdcall boost::reg_expression<char,class boost::regex_traits<char>,class std::allocator<char> ::can_start(char,unsigned char const *,unsigned char,struct boost::re_detail::_narrow_type const &)" (?can_start@?$reg_expression@DV?$regex_traits@D@boost@@V?$allocator@D@std@@@boost@@$$FKG_NDPBEEABU_narrow_type@re_detail@2@@Z) RexEngine.obj : error LNK2001: unresolved external symbol "void __stdcall boost::re_detail::reset_stack_guard_page(void)" (?reset_stack_guard_page@re_detail@boost@@$$FYGXXZ) RexEngine.obj : error LNK2001: unresolved external symbol "public: static void __stdcall boost::w32_regex_traits<char>::transform_primary(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (?transform_primary@?$w32_regex_traits@D@boost@@$$FSGXAAV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@ABV34@@Z) RexEngine.obj : error LNK2001: unresolved external symbol "public: static void __stdcall boost::w32_regex_traits<char>::transform(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > &,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (?transform@?$w32_regex_traits@D@boost@@$$FSGXAAV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@ABV34@@Z) RexEngine.obj : error LNK2001: unresolved external symbol "void __stdcall boost::re_detail::verify_options(unsigned int,enum boost::regex_constants::_match_flags)" (?verify_options@re_detail@boost@@$$FYGXIW4_match_flags@regex_constants@2@@Z) //-------------------------------------------------------------------------------- Any idea why these function calls failed to be linked. (does it has to do with the calling convention __fastcall being changed to __stdcall?) I have tried making BOOST_REGEX_CALL __cdecl to no avail. Help please ! Thanks in advance, Steve

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Re: [Boost-users] Serialization and null pointers
by boost＠iyates.com 06 Jul '05

06 Jul '05

Thanks. If I changed the order of the members being serialized it worked fine. Weird. However, I am running into a problem. I am using reference counted Smart Pointers. If I serialize the reference counter, then when it is loaded it will likely contain too large of a reference count because there were more objects referencing the pointer when it was saved than when it was loaded. However, it works fine it just doesn't properly delete the objects because the reference count never reaches 0. If I don't serialize the reference count then the objects try to delete themselves while boost is loading them from the file. I'm guessing because of the order everything happens, the final destination isn't increasing the reference count until after boost already dereferences it. Any suggestions? I thought maybe if there was a way to tell if the operation was saving during the serialize function I could just set the reference count to one, however that could be erroneous also if the same object being loaded has more than one smartpointer to the same object. I'm stumped... - Chris ----- Original Message ----- From: "Robert Ramey" <ramey(a)rrsd.com> To: boost-users(a)lists.boost.org Date: Tue, 5 Jul 2005 15:25:27 -0700 Subject: Re: [Boost-users] Serialization and null pointers > This shouldn't happen. > > you might try using an xml_archive so you can better see the output. This > will also check that the data saved and data loaded are "in sync". That is > that the same data is being saved and loaded. > > If all that fails, you'lll have to boil it down to a small example and send > it in > > Robert Ramey > > boost(a)iyates.com wrote: > > Hello, > > > > I have an object graph that is being serialized using a binary > > archive. It saves to the file fine, however a class member is being > > serialized is a null pointer. > > > > When I go to open the file, I get an access violation in > > basic_iarchive.cpp on line 393: > > > > bpis_ptr->load_object_ptr(ar, t, co.file_version); > > > > t is 0x00000000 > > > > Is there a way around this? Thank you. > > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > >

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Serialization and null pointers
by boost＠iyates.com 05 Jul '05

05 Jul '05

Hello, I have an object graph that is being serialized using a binary archive. It saves to the file fine, however a class member is being serialized is a null pointer. When I go to open the file, I get an access violation in basic_iarchive.cpp on line 393: bpis_ptr->load_object_ptr(ar, t, co.file_version); t is 0x00000000 Is there a way around this? Thank you.

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recursive read-write mutex?
by Austin Bingham 05 Jul '05

05 Jul '05

Is there any notion of recursive locking for the read-write mutex? Specifically, if a thread has a write-lock on a mutex, is there any way to have recursive read- or write-locks on that mutex pass immediately? Notionally, it seems that permission to write to something presumes permission to read it. However, when I try to read-lock a mutex which is already write-locked (in the same thread), I get deadlock. I would be happy to use the promote-demote functionality of the read_write_lock, but the following excerpt from the documentation scares me: "[The promote() function] throws boost::lock_error if . . . the lock cannot be promoted because another lock on the same mutex is already waiting to be promoted." This makes it sound like there is no way to guarantee that you can promote a lock, even with unbounded blocking. Is this the case? Thanks for any help on this. -- Austin Bingham "If I were creating the world I wouldn't mess about with butterflies and daffodils. I would have started with lasers, eight o'clock, Day One!" Evil

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How to copy binary file to dynamic bitset?
by Fujinobu Takahashi 05 Jul '05

05 Jul '05

Hello, I would like to try one-bit correlation between two one-bit sampling VLBI data files using powerful dynamic bitset library. (VLBI:Very Long Baseline Interferometer) A binary file japan.dat includes one-bit sampling data of a quasar received at a Japanese antenna and another binary file usa.dat includes one-bit sampling data of a same quasar received simultaneously at a US antenna. The bitset block size should be more than 10Mbits What kind of constructor codes should I write to copy the bit-pattern of each data file to each very long dynamic bitset? I am sorry but I could not find any good answer from Google search. I am looking forward to helpful answer in this mail-list. Very Thanks fuji

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