February 2007 - Boost-users - lists.preview.boost.org

Re: [Boost-users] [Filesystem] Folders with spaces in the name
by Nat Goodspeed 04 Feb '07

04 Feb '07

________________________________________ From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Nathan Pierluissi Sent: Saturday, February 03, 2007 5:53 PM To: boost-users(a)lists.boost.org Subject: [Boost-users] [Filesystem] Folders with spaces in the name I am having trouble using the /= operator to open folders with spaces in the name, ex. "My Documents" or "Program Files". Here is an example code: path full_path("c:\"); string Fname="Program Files"; full_path/=Fname; It works for any Fname (folder name) that doesn't have a space. Let me know if you need more information. Thanks in advance. [Nat] You didn't explain the nature of your 'trouble,' but if you're encountering exceptions, it's probably the default boost::filesystem::path syntax checker. Try explicitly disabling that rather than letting operator/= implicitly convert your string to boost::filesystem::path with the default checker, e.g. (neither compiled nor tested): full_path /= path(Fname, no_check);

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Re: [Boost-users] boost::serialization throws random exceptions
by Nat Goodspeed 03 Feb '07

03 Feb '07

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of Adrian Grigore > Sent: Saturday, February 03, 2007 9:11 AM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] boost::serialization throws random exceptions > > Robert Ramey wrote the following on 2/3/2007 1:30 AM: > > a) catch the archive exceptions and display an error message which > > describes what kind of exception has been thrown. > > I did something similar, but it is still a poor workaround. I save data > incrementally and rotate savefile names to make sure the player does not > lose all data, but just the changes since the last increment. Still, > losing all game progress since the last savefile increment is a major > turnoff for most players. [Nat] I think he was suggesting that you do that as a diagnostic measure to help discover and solve the problem you're encountering. I don't think he meant for you merely to put in the catch code and release the program. > > c) Just a while guess - thrown from load binary might suggest > > either the file isn't being opened binary, or the size of data > > being read isn't the same as what's being saved. > > I doubt that since there is only one save and one load routine in my > application. If I opened the file as text when saving and as binary when > loading this would always fail. But in my case everything is working > fine most of the time. [Nat] But you COULD be having troubles even if you open the file as text both for save and for load. In fact, the magic value 26 is a strong hint that this may be the trouble. A byte containing binary 26 may, in text mode, be interpreted as the character ctrl-Z -- which was the traditional MS-DOS EOF marker. Please try Robert's suggestion: ensure that you're opening the file using the binary flag both for saving and for loading the file.

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[Filesystem] Folders with spaces in the name
by Nathan Pierluissi 03 Feb '07

03 Feb '07

Greetings: I am having trouble using the /= operator to open folders with spaces in the name, ex. "My Documents" or "Program Files". Here is an example code: path full_path("c:\"); string Fname="Program Files"; full_path/=Fname; It works for any Fname (folder name) that doesn't have a space. Let me know if you need more information. Thanks in advance. -N. Pierluissi --------------------------------- Want to start your own business? Learn how on Yahoo! Small Business.

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Boost.MultiIndex iterator types
by Jonathan Wang 03 Feb '07

03 Feb '07

I have two multi_index_containers that are identical except for the ordering of the iterators. For example: struct Foo { long x, y; }; typedef boost::multi_index_container<Foo, indexed_by<ordered_non_unique<composite_key<Foo, member<Foo, long, &Foo::x>, member<Foo, long, &Foo::y> > > > > FooAscending; typedef boost::multi_index_container<Foo, indexed_by<ordered_non_unique<composite_key<Foo, member<Foo, long, &Foo::x>, member<Foo, long, &Foo::y> >, composite_key_compare<std::greater<long>, std::greater<long> > > > > FooDescending; The containers are indexed on composite keys of x and y - one in ascending order of y, the other in descending order. I have code that operates on iterators over these containers. Conveniently, the operation is identical, save for the ordering, so I can reuse the interesting code that works on these iterators. However, I am finding that the iterator types for the two containers are identical. Yet if I just define my overload for one of the iterators, everything works as expected. So my question is, is there a way to specify a generic iterator over a multi_index_container such that code on iterators can be reused in this way? It seems from the symbols gcc spits out that the iterator type depends only on the type held and the number of indices in the container (i.e. a container with a unique key on just Foo::x would also have its iterator type collide with FooAscending::iterator and FooDescending::iterator). Thanks, Jonathan

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Serialization of dynamic data
by Anders Sundman 03 Feb '07

03 Feb '07

Hi! About the boost::serialization library, what is the best way to handle dynamic data in classes? Any idéas, suggestions or caveats? I didn't manage to find anything about this in the docs. Consider the following sample class: struct Dyn { Dyn(int s) : data(0), size(s) { data = new char[size]; } ~Dyn() { delete data; } char* data; int size; private: friend class boost::serialization::access; template< class Archive > void serialize( Archive &ar, unsigned int ver ) { // -> ar & data; What to do here? ar & size; } }; What to do with the data pointer? Is there any way to determine (in the serialize function) if a serialization or "de-serialization" is taking place? And have different behaviours - either allocating a new char[x] or copying data to the archive? Is there any way to store dynamic data in an archive? Best regards, Anders Sundman

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some questions regarding ref
by abir basak 03 Feb '07

03 Feb '07

Hi, I want to have a few classes to be stored inside a vector by reference. I thought to use boost::ref for that purpose , instead of storing pointer. However I am facing some problem regarding the operator & . Here is a sample code which gives the problem, struct T2{ int x; T2(int x) :x(x){} }; int main(int argc,char** argv) { std::vector<boost::reference_wrapper<T2> > v; /// vector stores reference, rather than value. T2 t1 = 10; T2 t2 = 15; v.push_back(boost::ref(t1)); /// push ref to t1. v.push_back(boost::ref(t2)); ///push ref to t2. v[0].get().x = 5; ///get by ref & change. /// v[0].x = 5 ; this statement doesn't work! std::cout<<t1.x<<"\n"; ///change is reflected. return 0; } I am not sure why I have to use get for this purpose, while & operator is written for that purpose. Using MSVC 7.1 Even I face problem like this, struct T3{ T2 t2_; T3(int x) : t2_(x){} T2& operator&(){ return t2_; } }; std::vector<T3> v3; v3.push_back(T3(4)); v3.push_back(T3(5)); /// v3[0].x = 6; This doesn't work. (&v3[0]).x = 6; ///This works! Can anyone say a little detail about the problem ? -- Abir Basak, Member IEEE Software Engineer, Read Ink Technologies B. Tech, IIT Kharagpur email: abir(a)abirbasak.com homepage: www.abirbasak.com

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boost::serialization throws random exceptions
by Adrian Grigore 03 Feb '07

03 Feb '07

Hi, I'm experiencing occasional problems with boost::serialization when trying to write then read two simple classes, to a file. I am using boost 1.33.1 Most of the time everything's working fine, but sometimes the serialized data seems to be corrupt and boost::archive throws an exception when I try to load it back into the program. The error occurs about about 1 in 10 times I try this, and seems to depend on the exact values of the variables being saved. Here's a call stack of the thrown application: WxNonogram.exe!_CxxThrowException(void * pExceptionObject=0x00129680, const _s__ThrowInfo * pThrowInfo=0x00ff4954) + 0x50 bytes C++ WxNonogram.exe!boost::throw_exception<boost::archive::archive_exception>(const boost::archive::archive_exception & e={...}) + 0x40 bytes C++ WxNonogram.exe!boost::archive::basic_binary_iprimitive<boost::archive::binary_iarchive,std::basic_istream<char,std::char_traits<char> > >::load_binary(void * address=0x0012d05c, unsigned int count=4) + 0xaf bytes C++ WxNonogram.exe!boost::archive::basic_binary_iprimitive<boost::archive::binary_iarchive,std::basic_istream<char,std::char_traits<char> > >::load<int>(int & t=-858993460) + 0x31 bytes C++ WxNonogram.exe!boost::archive::load_access::load_primitive<boost::archive::binary_iarchive,int>(boost::archive::binary_iarchive & ar={...}, int & t=-858993460) + 0x2d bytes C++ WxNonogram.exe!boost::archive::detail::load_non_pointer_type<boost::archive::binary_iarchive,int>::load_primitive::invoke(boost::archive::binary_iarchive & ar={...}, int & t=-858993460) + 0x2b bytes C++ WxNonogram.exe!boost::archive::detail::load_non_pointer_type<boost::archive::binary_iarchive,int>::invoke(boost::archive::binary_iarchive & ar={...}, int & t=-858993460) + 0x2b bytes C++ WxNonogram.exe!boost::archive::load<boost::archive::binary_iarchive,int>(boost::archive::binary_iarchive & ar={...}, int & t=-858993460) + 0x2b bytes C++ WxNonogram.exe!boost::archive::basic_binary_iarchive<boost::archive::binary_iarchive>::load_override<int>(int & t=-858993460, int __formal=0) + 0x38 bytes C++ WxNonogram.exe!boost::archive::binary_iarchive_impl<boost::archive::binary_iarchive>::load_override<int>(int & t=-858993460, int __formal=0) + 0x31 bytes C++ WxNonogram.exe!boost::archive::detail::interface_iarchive<boost::archive::binary_iarchive>::operator>><int>(int & t=-858993460) + 0x38 bytes C++ WxNonogram.exe!boost::archive::detail::interface_iarchive<boost::archive::binary_iarchive>::operator&<int>(int & t=-858993460) + 0x39 bytes C++ WxNonogram.exe!NoNo::TGameProgress::TProfileState::serialize<boost::archive::binary_iarchive>(boost::archive::binary_iarchive & ar={...}, const unsigned int Version=4) + 0x7a bytes C++ Please help! I'm at a loss on how to proceed. Thanks for your time, Adrian -- Adrian Grigore adrian (AT) lobstersoft.com

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How to build Boost libs with stlportstld versions of stlport??
by Manish Mangal 03 Feb '07

03 Feb '07

Hi How Do I build boost libs with stlportstld dll of stlport when I build the debug versions of the boost libs. I do not want to use the stlportd versions . The command that I use for building boost is: jam "-sTOOLS=vc-8_0-stlport" "-sSTLPORT_VERSION=5.0.0" "-sSTLPORT_5.0.0_PATH=C:\SourceLibrary\STLport" "-sBUILD=debug release <runtime-link>dynamic <threading>multi <stlport-iostream>on <native-wchar_t>on" install Manish Mangal Software Engineer atlas(r) search Partner for Results 206-816-8349 // phone <mailto:t-Matt.Koch@AtlasSolutions.com> Manish.Mangal(a)AtlasSolutions.com www.AtlasSolutions.com <outbind://116-000000001368D4B5F8F6D0488191444C76FD7C9507008921F4CB773B0 545AAED425DEF553BC300003A3500100000DB0C51F64BED3447AA6EC585072C4EC300000 1E3B7A70000/jenniferh/Local%20Settings/Temporary%20Internet%20Files/OLK3 /www.AtlasSolutions.com> // web

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[Filesystem] Folders with spaces in the name
by Nathan Pierluissi 02 Feb '07

02 Feb '07

Greetings: I am having trouble using the /= operator to open folders with spaces in the name, ex. "My Documents" or "Program Files". Here is an example code: path full_path("c:\"); string Fname="Program Files"; full_path/=Fname; It works for any Fname (folder name) that doesn't have a space. Let me know if you need more information. Thanks in advance. -N. Pierluissi --------------------------------- Never Miss an Email Stay connected with Yahoo! Mail on your mobile. Get started!

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boost::interprocess::node_allocator problem (VC8, release build)
by alexmark 02 Feb '07

02 Feb '07

I have a problem with node_allocator. The "repro" code: #include <boost/interprocess/managed_external_buffer.hpp> #include <boost/interprocess/allocators/node_allocator.hpp> #include <boost/interprocess/containers/list.hpp> //////////////// using namespace boost::interprocess; //////////////// enum { A_SHARED_MEMORY_SIZE = 4096 * 50, A_POOL_SIZE = 512, }; //////////////// static char g_static_buffer[A_SHARED_MEMORY_SIZE]; static managed_external_buffer g_sharm (create_only, g_static_buffer, A_SHARED_MEMORY_SIZE); //////////////// typedef node_allocator<int, A_POOL_SIZE, managed_external_buffer::segment_manager> int_allocator_t; typedef list<int, int_allocator_t> IntList; //////////////// struct T { IntList int_list; // T () : int_list (int_allocator_t(g_sharm.get_segment_manager())) {} }; typedef node_allocator<T, A_POOL_SIZE, managed_external_buffer::segment_manager> tis_allocator_t; typedef list<T, tis_allocator_t> TList; //////////////// int main() { TList* p = g_sharm.construct<TList>(anonymous_instance)(tis_allocator_t(g_sharm.get_segment_manager())); try { enum { N = 2 }; // Create objects then delete them for (int n = 0; n < N; n++) { // Create T-type objects for (int i = 0; i < A_POOL_SIZE; i++) { p->push_back(T()); // push new object to the list } p->clear(); // Delete all T objects } } catch (bad_alloc &) { cout << "No memory" << endl; } g_sharm.destroy_ptr(p); return 0; } The problem is the folowing. If N > 1, on _second_ "pass" (n=1) the bad_alloc exception is thrown while pushing new T object to the list. Why? I supposed that on any "pass", except the first one, no new T-type objects are actually created in shared memory. They should be taken from the pool instead. I.e., if there's enough memory on the first "pass", it must be also enough on any other one. The problem is specific for Visual Studio 2005, when producing release build (all options carry their default values). Thanks, Alex.

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