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boost multithread C++ program design for low-latency large-data exchange
by Jack Bryan 25 Sep '11

25 Sep '11

Hi, I am trying to solve a network flow problem by C++ multithreading. Given a network (all nodes are connected by arcs, each arc is connected to 2 and only 2 ending nodes, one is input node and another is output node, each node can have multiple input arcs and output arcs), each node needs to do some computing and then exchange computing result data to its connected input and output nodes. Multiple nodes can be grouped into one task, which is run by one thread. In this way, the whole network computing workload can be partitioned into multiple tasks. All these tasks are pushed into a boost thread pool such that all threads can run the tasks at the same time. But, if a node (in a thread task) needs to do data exchange with another node (in another thread task), there is a synchronization problem. Data receiver needs to wait for data available in the data buffer of the data sender. My proram needs to partition the network such that each thread's task workload is assigned as evenly as possible. If all threads share the one-large data buffer structure, the program parallelism is not good because the critical section is too large. Some threads have to wait the the one-large data buffer structure unlocked even though the part of the data structure (which is useful to them ) has been available for read or write. For example, the one-large data buffer structure has the following buffer cells: cell1 , cell2, cell3 , cell4. When thread 1 is trying to write cell 1, it must lock the whole data buffer structure so that thread 2 cannot read or write cell 2 and so on. So, I want to break the one-large data buffer structure into multiple distinct data cells according to the thread number so that each cell holds the data only needed by one thread task. For example, if we have 2 threads, we create 2 data cells that hold data needed by the 4 thread separately. If we have 4 threads, we create 4 data cells that hold data needed by the 4 thread separately. and so on. My questions are: (1) How to design the data cell ? You can see that its size is based on the number of threads. (2) How to reduce synchronization overhead ? The critical section is small but the overhead of geting and releasing mutex may be very high if the inter-node data exchange frequency is high. (3) When a node's computing is done and data is written to its cell how to notify the data receiver node such that the notification messgae is only received by the waiting thread that run the receiver node computing task. All other unrelated nodes and threads are not impacted. The program is very time-sensitive and the latency of message exchange should be controlled very toughly and reduced as much as possible. Any help is really appreciated. Thanks

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Need a solid dictionary/map/query interface
by Michael Powell 24 Sep '11

24 Sep '11

Hello, A little background, we've got Visual Studio 2008 C++/CLI library through which we'd like to expose a dictionary-mapped data abstraction. We'd like to be able to ask some questions about the dictionary mapping, whether for its keys, values, or some combination thereof. I've got a strong background in C# particularly with regard to its Generic Collections and the Linq area. This is how I'd like to think of the dictionary questions. The rub of course is that the support for C++/CLI Linq is rather slim, if at all. Does boost offer something along these lines comparable to Linq? Thanks... Best regards, Michael

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boost::bind function with its input argument error
by Jack Bryan 24 Sep '11

24 Sep '11

Hi, I am trying to do multithreading by boost::bind. But, I got error: src/model.cpp:225: instantiated from here /boost_1_45_0v/include/boost/bind/mem_fn.hpp:333: error: pointer to member type void (Model::)(taskDataSPType&) incompatible with object type taskDataSPT1ype make: * [model.o] Error 1 Here is my code: void Model::runTask(taskDataSPType& myTask) {} taskDataSPType myTask; fifo_pool tp(thread_num); for (int i = 0 ; i < totalTaskNum ; +i) { taskQueue.wait_and_pop(myTask, i); myTask.taskID = i ; // run the typical iterations tp.schedule(boost::bind(&Model::runTask, &myTask)); } tp.wait(); In another header file, I have : typedef struct taskDataSPT1ype taskDataSPType; struct taskDataSPT1ype { int taskID; int startNode; int endNode; };

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boost::bind with derivated class
by Kraus Philipp 24 Sep '11

24 Sep '11

Hello, I'm using boost::bind for binding parameters to a method for calling a thread group: myclass::mymethod( const mysuperclass& myobj ) { bost::threadgroup mythreads; mythreads.create_thread( boost::bind( &myclass::mythreadmethod, this, boost::ref(myobj) ) ); } myclass::mythreadmethod( const mysuperclass myobj ) {} // I need a copy of the object, so I don't set the reference operator & mysuperclass is a pure virtual class. Now I create a derivate class with class myderivate : public mysuperclass {} and call myderivate y; myclass x; x.mymethod( y ); The compiler breaks with the error, that myobj is a class with pure virtual methods. How I can call the bind methods with the correct object? myobj is an object of the derivated class so I would "send them" to the methods. Thanks Phil

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[Enable-if] Selectively instantiating methods.
by Robert Jones 24 Sep '11

24 Sep '11

Hi All This doesn't work. template<typename T> struct S { typename disable_if<is_const<T>, int>::type mutating_method(); }; I understand why not, although only after the compiler threw it out, but obviously (in hindsight), the method itself is not a template, so can't be selectively instantiated. The question is whether and how I can achieve the effect I'm after, ie., that the method is not present if the struct is instantiated with a const type? Thx, Rob.

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using AM and PM with boost::posix_time newbie
by Adam Zedan 23 Sep '11

23 Sep '11

the following code works properly std::string ts("2002-01-20 10:27:30"); boost::posix_time::ptime t(boost::posix_time::time_from_string(ts)); std::cout << t.time_of_day() << "\n"; 1) Now i want to actually change the string to std::string ts("2002-01-20 10:27:30 AM"); but that wont work ?? Why any suggestions would be appreciated?? 2) also to display time i am using boost::posix_time::ptime pc(boost::posix_time::second_clock::local_time()); std::cout << pc.time_of_day() << "\n"; //output is 10:55:30 how could i make it display am/pm in the output ??

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Building boost.log
by Sillence, Martin (GE Oil & Gas) 23 Sep '11

23 Sep '11

Hi, We're using boost 1.47 and are interested in also using boost.log, I see some promising posts about using this in production: http://thread.gmane.org/gmane.comp.lib.boost.devel/221431 How are people building this, when we try (with the tunk from svn) it depends on boost.move which clashes with some of the functionality within boost 1.47 Is it possible to co-exist with 1.47 or are people using it with an older library? Thanks, M

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Boost::object_pool - Memory allocation problems
by Christian Berg 23 Sep '11

23 Sep '11

#include <boost/pool/object_pool.hpp> class test { test(void){}; public: std::vector<const int*> m_a1; int* m_b1; int* m_b2; const int* m_c1; const int* m_c2; const std::string* m_d1; unsigned int m_e1; unsigned int m_e2; unsigned char m_f1; unsigned char m_f2; unsigned char m_f3; unsigned char m_f4; }; static boost::object_pool<test> s_my_pool; int main(int argc, char* argv[]) { int max = 2097120; for(int i = 0; i < max; i++) { test* tst_c = s_my_pool.construct(test()); } Consider the code above. Compiled with Visual Studio 2010. The purpose of the class is not important. It is its size (48 bytes) that matters. The goal is to use object_pool to minimize memory usage. When running this code the memory rises with just a few bytes more than the needed 48 bytes * 2.097.120 = 100.661.760 bytes, hence the object_pool seems to be working fine. But if I increase the number of elements created by one (to 2097121) the memory use rises to a massive 200.000.000+ bytes. It seems that the object_pool has reached a threshold and that the strategy then is to double the allocated memory. But this can't be right, can it? If so the object_pool is useless because it's using more memory than a simple test* tst = new test(); would have done. Why is object_pool acting like this and is there a way to change the behavior? PS! The threshold value is not exactly the same in another application I have made, but it is pretty close. Best Regards Christian Berg

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Cross-compiling: Errors compiling with qcc toolset for qnx target-os from linux host
by Félix Robles 23 Sep '11

23 Sep '11

Hi, I've got KUbuntu 64bits installed: Linux findeton-PC 2.6.38-11-generic #48-Ubuntu SMP Fri Jul 29 19:02:55 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux I want to compile boost using qcc toolset for a qnx target-os from a linux host, so I execute: $ ./bootstrap.sh And it goes fine, it uses the gcc compiler, not qcc, because I want to execute b2 in my linux machine. Then I use the following command: $ ./b2 --build-dir=/home/findeton/boost_1_47_0/ toolset=qcc target-os=qnx --build-type=complete --layout=tagged -q -a And this is the kind of output I get: qcc.compile.c++ /home/findeton/boost_1_47_0/boost/bin.v2/libs/python/build/qcc/debug/link-static/target-os-qnx/numeric.o In file included from ./boost/integer_fwd.hpp:17, from ./boost/integer.hpp:18, from ./boost/function/function_base.hpp:21, from ./boost/function/detail/prologue.hpp:17, from ./boost/function/function_template.hpp:13, from ./boost/function/detail/maybe_include.hpp:13, from ./boost/function/function0.hpp:11, from ./boost/python/errors.hpp:13, from ./boost/python/handle.hpp:11, from ./boost/python/converter/arg_to_python_base.hpp:7, from ./boost/python/converter/arg_to_python.hpp:14, from ./boost/python/call.hpp:15, from ./boost/python/object_core.hpp:14, from ./boost/python/object.hpp:9, from ./boost/python/tuple.hpp:10, from ./boost/python/numeric.hpp:10, from libs/python/src/numeric.cpp:6: ./boost/cstdint.hpp:74: error: 'intleast8_t' in namespace '::' does not name a type ./boost/cstdint.hpp:75: error: 'intfast8_t' in namespace '::' does not name a type ./boost/cstdint.hpp:76: error: 'uintleast8_t' in namespace '::' does not name a type ./boost/cstdint.hpp:77: error: 'uintfast8_t' in namespace '::' does not name a type ./boost/cstdint.hpp:79: error: 'intleast16_t' in namespace '::' does not name a type ./boost/cstdint.hpp:80: error: 'intfast16_t' in namespace '::' does not name a type ./boost/cstdint.hpp:81: error: 'uintleast16_t' in namespace '::' does not name a type ./boost/cstdint.hpp:82: error: 'uintfast16_t' in namespace '::' does not name a type ./boost/cstdint.hpp:84: error: 'intleast32_t' in namespace '::' does not name a type ./boost/cstdint.hpp:85: error: 'intfast32_t' in namespace '::' does not name a type ./boost/cstdint.hpp:86: error: 'uintleast32_t' in namespace '::' does not name a type ./boost/cstdint.hpp:87: error: 'uintfast32_t' in namespace '::' does not name a type ./boost/cstdint.hpp:91: error: 'intleast64_t' in namespace '::' does not name a type ./boost/cstdint.hpp:92: error: 'intfast64_t' in namespace '::' does not name a type ./boost/cstdint.hpp:93: error: 'uintleast64_t' in namespace '::' does not name a type ./boost/cstdint.hpp:94: error: 'uintfast64_t' in namespace '::' does not name a type cc: /opt/qnx650/host/linux/x86/usr/lib/gcc/i486-pc-nto-qnx6.5.0/4.4.2/cc1plus error 1 "QCC" -Wc,-ftemplate-depth-128 -gstabs+ -O0 -Wc,-fno-inline -DBOOST_ALL_NO_LIB=1 -DBOOST_PYTHON_SOURCE -DBOOST_PYTHON_STATIC_LIB -I"." -I"/usr/include/python2.7" -c -o "/home/findeton/boost_1_47_0/boost/bin.v2/libs/python/build/qcc/debug/link-static/target-os-qnx/numeric.o" "libs/python/src/numeric.cpp" ...failed qcc.compile.c++ /home/findeton/boost_1_47_0/boost/bin.v2/libs/python/build/qcc/debug/link-static/target-os-qnx/numeric.o... qcc.compile.c++ /home/findeton/boost_1_47_0/boost/bin.v2/libs/python/build/qcc/debug/link-static/target-os-qnx/list.o In file included from ./boost/integer_fwd.hpp:17, from ./boost/integer.hpp:18, from ./boost/function/function_base.hpp:21, from ./boost/function/detail/prologue.hpp:17, from ./boost/function/function_template.hpp:13, from ./boost/function/detail/maybe_include.hpp:13, from ./boost/function/function0.hpp:11, from ./boost/python/errors.hpp:13, from ./boost/python/handle.hpp:11, from ./boost/python/converter/arg_to_python_base.hpp:7, from ./boost/python/converter/arg_to_python.hpp:14, from ./boost/python/call.hpp:15, from ./boost/python/object_core.hpp:14, from ./boost/python/object.hpp:9, from ./boost/python/list.hpp:10, from libs/python/src/list.cpp:5: ./boost/cstdint.hpp:74: error: 'intleast8_t' in namespace '::' does not name a type ./boost/cstdint.hpp:75: error: 'intfast8_t' in namespace '::' does not name a type ./boost/cstdint.hpp:76: error: 'uintleast8_t' in namespace '::' does not name a type ./boost/cstdint.hpp:77: error: 'uintfast8_t' in namespace '::' does not name a type ./boost/cstdint.hpp:79: error: 'intleast16_t' in namespace '::' does not name a type ./boost/cstdint.hpp:80: error: 'intfast16_t' in namespace '::' does not name a type ./boost/cstdint.hpp:81: error: 'uintleast16_t' in namespace '::' does not name a type ./boost/cstdint.hpp:82: error: 'uintfast16_t' in namespace '::' does not name a type ./boost/cstdint.hpp:84: error: 'intleast32_t' in namespace '::' does not name a type ./boost/cstdint.hpp:85: error: 'intfast32_t' in namespace '::' does not name a type ./boost/cstdint.hpp:86: error: 'uintleast32_t' in namespace '::' does not name a type ./boost/cstdint.hpp:87: error: 'uintfast32_t' in namespace '::' does not name a type ./boost/cstdint.hpp:91: error: 'intleast64_t' in namespace '::' does not name a type ./boost/cstdint.hpp:92: error: 'intfast64_t' in namespace '::' does not name a type ./boost/cstdint.hpp:93: error: 'uintleast64_t' in namespace '::' does not name a type ./boost/cstdint.hpp:94: error: 'uintfast64_t' in namespace '::' does not name a type cc: /opt/qnx650/host/linux/x86/usr/lib/gcc/i486-pc-nto-qnx6.5.0/4.4.2/cc1plus error 1 "QCC" -Wc,-ftemplate-depth-128 -gstabs+ -O0 -Wc,-fno-inline -DBOOST_ALL_NO_LIB=1 -DBOOST_PYTHON_SOURCE -DBOOST_PYTHON_STATIC_LIB -I"." -I"/usr/include/python2.7" -c -o "/home/findeton/boost_1_47_0/boost/bin.v2/libs/python/build/qcc/debug/link-static/target-os-qnx/list.o" "libs/python/src/list.cpp" ...failed qcc.compile.c++ /home/findeton/boost_1_47_0/boost/bin.v2/libs/python/build/qcc/debug/link-static/target-os-qnx/list.o... [ And after some of those, then I get some of this kind : ] qcc.compile.c++ /home/findeton/boost_1_47_0/boost/bin.v2/libs/serialization/build/qcc/release/target-os-qnx/threading-multi/binary_iarchive.o In file included from ./boost/serialization/extended_type_info_typeid.hpp:34, from ./boost/archive/detail/iserializer.hpp:47, from ./boost/archive/detail/interface_iarchive.hpp:22, from ./boost/archive/detail/common_iarchive.hpp:23, from ./boost/archive/basic_binary_iarchive.hpp:31, from ./boost/archive/binary_iarchive_impl.hpp:22, from ./boost/archive/binary_iarchive.hpp:20, from libs/serialization/src/binary_iarchive.cpp:14: ./boost/serialization/factory.hpp:28: error: '::va_list' has not been declared cc: /opt/qnx650/host/linux/x86/usr/lib/gcc/i486-pc-nto-qnx6.5.0/4.4.2/cc1plus error 1 "QCC" -Wc,-ftemplate-depth-128 -O3 -Wc,-finline-functions -Wc,-Wno-inline -shared -DBOOST_ALL_NO_LIB=1 -DBOOST_SERIALIZATION_DYN_LINK=1 -DNDEBUG -I"." -c -o "/home/findeton/boost_1_47_0/boost/bin.v2/libs/serialization/build/qcc/release/target-os-qnx/threading-multi/binary_iarchive.o" "libs/serialization/src/binary_iarchive.cpp" ...failed qcc.compile.c++ /home/findeton/boost_1_47_0/boost/bin.v2/libs/serialization/build/qcc/release/target-os-qnx/threading-multi/binary_iarchive.o... qcc.compile.c++ /home/findeton/boost_1_47_0/boost/bin.v2/libs/serialization/build/qcc/release/target-os-qnx/threading-multi/binary_oarchive.o In file included from ./boost/serialization/extended_type_info_typeid.hpp:34, from ./boost/archive/detail/oserializer.hpp:38, from ./boost/archive/detail/interface_oarchive.hpp:23, from ./boost/archive/detail/common_oarchive.hpp:22, from ./boost/archive/basic_binary_oarchive.hpp:34, from ./boost/archive/binary_oarchive_impl.hpp:23, from ./boost/archive/binary_oarchive.hpp:21, from libs/serialization/src/binary_oarchive.cpp:14: ./boost/serialization/factory.hpp:28: error: '::va_list' has not been declared ¿What is wrong, how can I solve it?

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Re: [Boost-users] [Enable-if] Selectively instantiating methods.
by Ivan Le Lann 23 Sep '11

23 Sep '11

----- "Robert Jones" <robertgbjones(a)gmail.com> a écrit : > Hi All > > > This doesn't work. > > > > template<typename T> struct S > { > typename disable_if<is_const<T>, int>::type mutating_method(); > } ; > > This thread might be related : http://lists.boost.org/Archives/boost/2011/08/184454.php Hope this helps, Ivan

1 0

Compilation of boost on HP-UX 11iv3 using aCC
by Pravar 23 Sep '11

23 Sep '11

Hi All, I am trying to compile boost 1.45.0 on HP-UX with HP compiler ( acc ) having version A.06.26. OS version : HP-UX 11iV3 on IA-64 _Question_ : Does anyone has experience of compiling boost with aCC compiler ? Does boost listed aCC as supported compilers ? As I tried to compile and compilation failed at points generating errors. I need to use boost for some production level software and if such issues occur, I wonder i may not be able to use boost on HP-UX. I earlier thought for using gcc, but it is no longer supported on HP-UX and it is risky to use it for production work. Please provide some directions in this regard. It will be immensely helpful for me. Thanks and Best Regards, Pravar DISCLAIMER: ----------------------------------------------------------------------------------------------------------------------- The contents of this e-mail and any attachment(s) are confidential and intended for the named recipient(s) only. It shall not attach any liability on the originator or NECHCL or its affiliates. Any views or opinions presented in this email are solely those of the author and may not necessarily reflect the opinions of NECHCL or its affiliates. Any form of reproduction, dissemination, copying, disclosure, modification, distribution and / or publication of this message without the prior written consent of the author of this e-mail is strictly prohibited. If you have received this email in error please delete it and notify the sender immediately. . -----------------------------------------------------------------------------------------------------------------------

2 2

[Phoenix] expression does not name a type
by Júlio Hoffimann 23 Sep '11

23 Sep '11

Dear all, I can't understand why this test case is not compiling: #include <boost/function.hpp>#include <boost/phoenix/core/argument.hpp>#include <boost/phoenix/operator.hpp>#include <iostream> using namespace boost::phoenix::placeholders; expression::argument<1>::type X; int main ( int argc, char *argv[] ){ boost::function<int(int)> f; f = if_else( X == 0, X, X*2 ); std::cout << f(0) << f(12) << std::endl; return 0;} // ---------- end of function main ---------- The error message says 'expression' does not name a type. I've tried to explicitly play with boost::phoenix namespaces, but doesn't work. Appreciate any help, Júlio. P.S.: Boost 1.47 / GCC 4.5

2 2

[Intrusive] Using a mutex-guarded smart pointer to achieve thread-safety
by Ioannis Papadopoulos 22 Sep '11

22 Sep '11

Hi, I was looking over Boost.Intrusive and specifically the section regarding smart pointers. I am mostly interested in the linked lists, so I don't have any need for size(); auto-unlink however is extremely useful to me. If I replace the default pointer with my thread-safe smart_ptr-like type (for example a wrapper that instead of doing reference counting, it guards the pointers with a mutex), do you think that the resulting intrusive container will be thread-safe? Has anyone attempted anything similar? Thanks

2 1

Interval Timer
by asif saeed 22 Sep '11

22 Sep '11

Hi, I need an interval timer to continuously call my callback function after every n milliseconds/seconds for ever once I set it up. I also need the ability to kill/cancel the timer. Does Boost provide such a facility now? Sincerely, Asif

3 3

[Timer] Using progress timers.
by Robert Jones 21 Sep '11

21 Sep '11

Hi All, > cat progress.cpp #include <boost/progress.hpp> int main( ) { boost::progress_timer t; sleep( 5 ); return 0; } > g++ progress.cpp > ./a.out 0.00 s I was expecting a number >= 5.00 s! What am I missing? Thx, Rob.

5 5

[Test/Build] has there been added a feature to specify the working directory of a unit-test?
by Thorsten Ottosen 21 Sep '11

21 Sep '11

Hi Everybody, This problem was dicussed some time ago in this thread: http://boost.2283326.n4.nabble.com/Current-directory-in-unit-tests-td269491… Have a solution been implemented to this problem? regards Thorsten

1 0

Passing format strings to printing tuples
by Krzysztof Żelechowski 21 Sep '11

21 Sep '11

The current tuple output mechanism wants me to say cout << formatting_manipulator << tuple; The expression (cout << formatting_manipulator) return an "embossed" cout, but currently it returns just cout with internal settings modified. The call must change things allocated within cout, like the standard manipulators do; although it is supported by the standard output, I find this approach so CFront-ish. How about using the syntax (cout << format_specification (tuple)) instead? Or even (cout << tuple / format_specification)? Chris

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Re: [Boost-users] [asio] Interval Timer
by Andrew Holden 21 Sep '11

21 Sep '11

On Wednesday, September 21, 2011 8:15 AM, asif saeed wrote: > I need an interval timer to continuously call my callback function > after every n milliseconds/seconds for ever once I set it up. I > also need the ability to kill/cancel the timer. Does Boost provide > such a facility now? You could assemble that timer using asio's deadline_timer http://www.boost.org/doc/libs/1_47_0/doc/html/boost_asio/reference/deadl ine_timer.html The deadline_timer calls a callback at a specified time. Your callback would need to calculate the time of the next callback and restart the timer. Perhaps the following pseudocode could get you started: Public data members: * deadline_timer::duration_type trigger_interval * bool is_killed Private data members: * deadline_timer::time_type next_trigger * deadline_timer the_timer Constructor: is_killed = false Set trigger_interval next_trigger = now + trigger_interval Initialize the_timer Call the_timer.expires_at Callback: if (! is_killed and no errors happened) { next_trigger += trigger_interval Call the_timer.expires_at Do your processing }

1 0

from a variant to class with members templated over the variant types
by Olivier Tournaire 21 Sep '11

21 Sep '11

Hi all, I am not sure if the title is self explanatory, so, let me show an example of the goal. I have: variant<type1, type2, type3> v; I want: struct { anobject<type1> _type1_object; anobject<type2> _type2_object; anobject<type3> _type3_object; } Is there a way to do such a thing with boost pp (or something else)? Regards, Olivier

2 1

Re: [Boost-users] [Timer] Using progress timers
by Alex Perry 21 Sep '11

21 Sep '11

On Wed, 21 Sep 2011 11:47:35 +0100 Robert Jones wrote:- > cat progress.cpp > > #include <boost/progress.hpp> > > int main( ) > { > boost::progress_timer t; > > sleep( 5 ); > > return 0; > } > > > g++ progress.cpp > > > ./a.out > 0.00 s > > I was expecting a number >= 5.00 s! What am I missing? Not sure if its any help but above does work on windows with appropriate change to sleep >type test.cpp #include <boost/progress.hpp> #include <windows.h> int main( ) { boost::progress_timer t; Sleep( 5000 ); return 0; } >cl test.cpp Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 16.00.30319.01 for 80x86 Copyright (C) Microsoft Corporation. All rights reserved. test.cpp Microsoft (R) Incremental Linker Version 10.00.30319.01 Copyright (C) Microsoft Corporation. All rights reserved. /out:test.exe test.obj C:\workspace\Test>test 5.00 s HTH Alex

1 0

[UTF] documentation of runtime configuration programmatically
by gast128 20 Sep '11

20 Sep '11

Hello all, the documentation of Boost.Test contains the following sentence "The UTF provides two ways to set a parameter at runtime: by specifying a command line argument and by setting an environment variable. The command line argument always overrides the corresponding environment variable." However it does not explain how. For example if I add this line to my code it crashes: boost::runtime::env::get<bool>("BOOST_TEST_AUTO_START_DBG"); Anyone?

1 1

[Serialization]Serialization of nested stl object
by Kangkook Jee 20 Sep '11

20 Sep '11

Hi, all A member of a target class, where one STL object (map) includes another (set), prevent the code from being built properly and the error message urges me to implement *serialize* method for pair<string*, set<unsigned>>. What is the typical way of implementing serialization using boost for this kind of data structures? * Code snippet class B { … map<const string*, set<unsigned> > lines; .. template<class Archive> void serialize (Archive & ar, const unsigned int version) { ar & lines; … * Build error message /opt/local/include/boost/serialization/access.hpp:118: error: ‘class std::map<const std::string*, std::set<unsigned int, std::less<unsigned int>, std::allocator<unsigned int> >, std::less<const std::string*>, std::allocator<std::pair<const std::string* const, std::set<unsigned int, std::less<unsigned int>, std::allocator<unsigned int> > > > >’ has no member named ‘serialize’ Thanks for your help in advance, /Kangkook

2 4

shared_ptr design question
by John M. Dlugosz 20 Sep '11

20 Sep '11

I'm wondering why there is not an efficient built-in way to check whether two things (e.g. a shared_ptr and a weak_ptr, but any combination should work) refer to the same object. In my implementation, I found that a handy thing to have. In changing code that uses a different home-brew smart pointer, I have to achieve this. The only way I see is to first resolve the weak pointer, and then compare the get() from each. That needlessly yoyo's the reference count, which is a horribly expensive atomic operation. I find that in the new C++ standard it refers to a owner_before ordering function, which is a bit more obscure than just comparing the pointers. So I'm wondering why this is not provided. Is there some reason why the feature is obscured, for portability? —John

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gdb pretty printers
by Jonathan Brannan 20 Sep '11

20 Sep '11

Are there any pretty printers for the more complex boost types? Specifically I'm looking for boost::multi_index printers as looking at in debug seems unhelpful.

2 2

Flow rate dimensional analysis
by Michael Powell 19 Sep '11

19 Sep '11

Boost::units users, I am trying to perform a flow rate through an orifice calculation (Volume per Time or L^3T^-1) using the following dimensional analysis: Q = Cf * A * sqrt( 2 * abs(P1-P2) ) On paper the dimensional analysis works out correctly. I know we should be receiving a L^3T^-1 consequent to the calculation. If I just take this on one line, it seems to compile: __C_flow * __a_orifice * boost::units::sqrt(__two * __p_diff / __d); Where __a_orifice is the area of the orifice, __p_diff is the pressure differential (absolute value), and __d is the mass density. __C_flow (coefficient of flow through orifice) and __two (2.0) are both dimensionless. In terms of units quantities, these are all defined as quantity<si::area>, quantity<si::pressure>, quantity<si::mass_density>, and quantity<si::dimensionless>, to start with. I think my flow-rate dimension and/or unit must be incorrect, but I am failing to see why in order to know what to do to correct the error. typedef boost::units::derived_dimension<boost::units::length_base_dimension,3 ,boost::units::time_base_dimension,-1>::type flow_rate_dimension; typedef boost::units::unit<cs::units::flow_rate_dimension,boost::units::si::system> flow_rate; When I take: si::flow_rate __fr = __C_flow * __a_orifice * boost::units::sqrt(__two * __p_diff / __d); I am receiving the following compiler error as my clue... Error 1 error C2440: 'initializing' : cannot convert from 'boost::units::quantity<Unit,Y>' to 'boost::units::quantity<Unit,Y>' c:\Source\Simulations\CS.Calculations.Managed\Calculators\Calculator.cpp 461 CS.Calculations.Managed I'd like to set this up in as base a dimension as possible because later on we'll be introducing unit views, converting from base units to a view unit, or unit system, along these lines, but if we have to specify this in specific unit terms, so be it. We'll worry about unit conversions later on. Best regards, Michael Powell

2 6

How do you handle state-independent events efficiently in MSM?
by Peter Gissel 19 Sep '11

19 Sep '11

I have a state machine that has a large number of event types but only a few different states. Some of the events can be received regardless of the state and the same action is taken regardless of which state the machine is in, so the event is really unrelated to the state. I there an efficient way of handling the events that are state independent rather than defining a transition from every possible state for each state independent event? A number of the events do transition the state machine and depend on the current state, so a transition is necessary. But if no state change is required for the event and the current state is not important, I'm not sure how to define event handling without defining a transition from all possible states. This winds up creating a much larger number of transitions than I really need, and a much longer compile time than I would like. I am looking for some way to handle these states that would still give me good run time speed, put not pay the penalty that defining a large number of transitions would impose. Thanks! Peter Gissel

2 6

threads: shared lock question
by Mark Higgins 19 Sep '11

19 Sep '11

I'm new to threads and boost, so I'm sure this is a real newbie question and hopefully quite easy to answer! I'm trying to set up a pool of threads that do a calculation, and I want to wait for those calculations to finish. Normally I'd do thread_group.join_all() to wait for the threads to exit - but in this case I want my threads hanging around so that I can redo that calculation over and over again when I ask it to do. What's the best way to signal back to the main thread that all calculations are complete? Should I use a barrier?

5 4

What concepts/interface must the element type of multi_index_container<> support?
by Chris Cleeland 19 Sep '11

19 Sep '11

I'm trying to use boost::multi_index_container on a type that I've defined. I want the container to have two indices: 1. insertion order 2. hashed_unique Further, I want the hash to use an sha1 hash value, which I have represented as a struct. So, I have something like the following: struct sha1_hash_value { ... }; class MyRecord { public: ... sha1_hash_value hash() const { return _sha1_hash; } ... private: sha1_hash_value _sha1_hash; }; using namespace boost::multi_index; typedef boost::multi_index_container< MyRecord, indexed_by< sequenced<>, hashed_unique<const_mem_fun<MyRecord,sha1_hash_value,&MyRecord::hash> > > > RecordSet; When I compile this, I get lots of complaints regarding the conversions to/from the 'sha1_hash_value' type. I understand that I need to define appropriate member functions or specializations for this type. What I would like to know is what those member functions/specializations are and where that is documented so that I don't have to decipher compiler error gibberish iteratively and just cross my fingers that the errors are really about missing functionality and not about misuse. FWIW, if I change sha1_hash_value to a 'long', the code compiles, so it doesn't appear as if I'm completely misusing multi_index_container<>, though I'm certainly still open to that possibility as well. Thanks for any help. The brick wall I'm banging my head against is really starting to hurt.

2 2

boost::bind replacements
by Littlefield, Tyler 18 Sep '11

18 Sep '11

Hello all: I really like boost::bind because I use an event system in my game engine, and it allows me to bind callbacks in classes, rather than having everything as global functions, like they were before. My problem is this. Boost::bind incurs a lot of overhead, both during compilation and in binary size. Is there any way to decrease this? If not, I'm curious if someone could explain how boost::bind works so that I can create my own? I understand function objects can hold function pointers and boost::bind returns a function object, but I'm really confused as to how placeholders work. -- Take care, Ty Web: http://tds-solutions.net The Aspen project: a light-weight barebones mud engine http://code.google.com/p/aspenmud Sent from my toaster.

4 4

[fusion] [range] range::erase vs. fusion::erase
by Nathan Ridge 17 Sep '11

17 Sep '11

Hi, I have an std::vector<S> and I use boost::erase() from Boost.Range on it. Now I changed S to be a Fusion sequence type, and as a result, boost::fusion::erase() is being found by ADL and called instead of boost::range::erase(). Which of course gives all kinds of errors because std::vector is not a Fusion sequence. Is there a way to avoid this, besides qualifying every call to boost::erase() as boost::range::erase()? Basically I want to disable the finding of boost::fusion:: algorithms by ADL. Thanks, Nate

2 2

Question on std::binary_function template arguments
by John M. Dlugosz 17 Sep '11

17 Sep '11

You may recall my earlier question asking if there was an easy way to "bind" a member function to a weak_ptr. Looking at the lower-level STL features, I came up with this idea, to prepare an adaptor in the same manner as mem_fun and mem_fun_ref. Generalizing the idea, it takes a member function and produces a functor that takes the object as a first argument, for various ways of presenting the object. I extended it with mem_fun_weak, where the resulting functor is called with a weak_ptr as the first argument. Below is one form (the one I need). To work along with the other STL primitives, there are a total of 4 forms (const/non-const, one arg or no args). That doesn't have arbitrary signatures like the more general "bind", which is something I'd like to discuss further. For now, my question concerns the first template argument to std::binary_function. Looking at the declarations for the standard mem_fun1_t and mem_fun1_ref_t, I don't know if this should be: 1) the full type passed as the first argument to the resulting functor, 2) such, but without the final &, 3) just the object's type, 4..n) something else? Can someone clarify that for me? Here is my code (using #1 above): template <typename Result, typename Type, typename Arg> class mem_fun1_weak_t : public std::binary_function<const std::tr1::weak_ptr<Type>&, Arg, Result> { Result (Type::*p )( Arg ); public: explicit mem_fun1_weak_t( Result (Type::*Pm )( Arg ) ) : p(Pm) {} Result operator() (const std::tr1::weak_ptr<Type>& left, Arg right) const { std::tr1::shared_ptr<Type> sp (left.lock()); if (sp) { Type* object= sp.get(); // shared_ptr doesn't overload operator->*. return (object->*p)(right); } else return Result(); } }; template<typename Result, typename Type, typename Arg> mem_fun1_weak_t<Result, Type, Arg> mem_fun_weak (Result ( Type::*Pm )( Arg ) ) { return mem_fun1_weak_t<Result, Type, Arg> (Pm); } Thanks, —John

3 4

complex matrix operations - eigen decomposition, singular value decomposition, complex inverse, cholesky decomposition etc
by sairamesh raghuraman 17 Sep '11

17 Sep '11

Hello, I am looking for a C++ library that has routines for a variety of complex matrix decompositions (eigen, cholesky, singular value etc) and even complex matrix inverse, principal matrix logarthm of a complex matrix etc. And the matrices which I am talking are pretty huge..can go upto 1024 x 1024 x 32. I have already found a library that can do all of the above..used it..it works fine..but a disadvantage is that it cannot handle multidimensional arrays. Now the question is, does Boost C++ library have functions for the above? Looking forward to a reply and thanks in advance Ramesh

2 1

[Boost.Log] Compiling
by Leo Cacciari 17 Sep '11

17 Sep '11

Hi, I'm working on an application that'll use the boost libraries, and I thought using boost.Log for logging (yes, I'm aware the API will change when boost.Log will be included in the boost distribution). My problems start when I try to compile the library. I downloaded the source and copied the relevant files in a 1.42.0 source tree (1.42.0 is the default version of boost on my Ubuntu 10.10 system) then run bjam --with-log This works, and it also builds a bunch of other libraries, the ones Boost.Log depends upon i.e., as per Boost.Log documentation, Boost.Filesystem, Boost.System, Boost.DateTime, Boost.Thread and Boost.Regex. However, these libraries are already installed on my system, using my distribution packages. Installing the newly compiled version of these libraries alongside the pre-existing ones will confuse my linker, and replacing the latter with the former will confuse my package manager... To me the alternatives seem to be the following: - install a full boost distribution replacing the one furnished by Ubuntu (plus: I could use 1.47, minus: I prefer using software in the Ubuntu repositories, if possible) - manually copying the compiled libboost_log* from the stage directory and header files from the boost/log directory into the target directory, skipping the bjam installation phase (pro: quickly done, minus: I'm not sure that the install process does not perform other tasks, beyond copying the files and running ldconfig, nor I'm sure that there is no compatibility issues) Obviously, I could miss other approach, especially one that simply told bjam to use the already installed libraries instead of compiling new versions. Could anyone offer suggestions? -- Leo Cacciari Aliae nationes servitutem pati possunt populi romani est propria libertas

2 1

"apply" member function over collection
by John M. Dlugosz 17 Sep '11

17 Sep '11

Consider this: // new way, so far so good boost::range::for_each (mylist, std::tr1::bind(&C::foo, _1)); // original: // for(Collection::iterator fi = mylist.begin(); fi != mylist.end(); ++fi) { // Collection::reference item = *fi; // item->foo(); // } I've got a zillion of these one-shot "for" loops, and I was able to change this sample to use a range::for_each. But, it's still too ackward and will be unfamiliar to other users, so it has to be "sleek or bust"! The item type is actually a smart pointer. Is there a more succinct way of writing it, without needing the extra placeholder to be mentioned? The for_each works find as an "apply" except that the member function needs to be adapted; it won't do that by itself. I found that boost::range::for_each (Filters, std::tr1::mem_fn(&VseeMediaFilter::Uninitialize)); compiles too, even though I'll be passing a smart pointer to the resulting adapted function. But, as mentioned on another thread, mem_fn is deprecated? How might I write this more tersely, or provide an 'apply' utility of my own that does what I want? Thanks, —John

1 0

Re: [Boost-users] boost 1.47: gcc file dependency generation trips over BOOST_PARAMETER_MAX_ARITY
by Ivan Le Lann 17 Sep '11

17 Sep '11

----- "Ytsen de Boer" <yrdeboer(a)gmail.com> a écrit : > Thank you for your answer. > I believe we are not on the same page. > Obviously, when I define the max arity to a value of 7 or more, the > preprocessor will finish properly. > > But the point I am trying to make is more subtle, namely, that the > generation of the project dependencies has not a thing to do with the > boost max arity. I think it does actually. How could gcc track inclusions without preprocessing ? #ifdef USE_LIB_A # include "a.h" #else # include "b.h" #endif It seems very dangerous to me to use "-MMD" with different preprocessor definitions than at real compile time. But I'm not an expert. Anyway : > > I don't know what the boost max arity means or what its for, but it > seems to me that it is a run time variable. Have you checked that ? My guess is that it is a compile time variable controlling the number of template arguments for a particular class or function. Pure compile time. Regards, Ivan

3 2

[qi] Get line number of an on_error handler from an ifstream iterator
by boost_mailinglist＠gmx.de 16 Sep '11

16 Sep '11

Hello, can anyone of you give me a hint, how I can get the line number of the input file inside the on_error handler where the parsing error happens? Full source is atttached as file.cpp. bool test(Iterator first, Iterator last) { qi::rule<Iterator>start; start.name("start"); start=*(eps>char_('a')>>eol); on_error<fail> ( start , std::cout << val("Error! Expecting ") << _4 << val(" here(") //linenumber insert << val("): \"") << construct<std::string>(_3, _2) << val("\"") << std::endl ); bool r = qi::parse(first,last,start); if (r && first == last){ return true; } else{ return false; } } Best regards

2 2

Re: [Boost-users] [serialization] Implementing a JSON archive
by Stepan Seycek 16 Sep '11

16 Sep '11

Hi Leo, what about JSONCPP (http://jsoncpp.sourceforge.net/) We use it for interfacing with CouchDB. BR, Stepan On 2011-09-16 11:06, Leo Cacciari wrote: > Hi, > for a project I'm working on, I need to be able to send JSON-encoded > objects on a network connection. I though that extending the > xml_[io]archive classes could do the trick, given that JSON, just like > xml, is based on representing an object by a collection of NVPs > (name-value pairs). However, I was unable to find an explication on > _how_ to extend that class, and I lost myself very quickly when I tried > to follow the code in the source. > > Thus I'm wondering... > > First, should I actually modify xml_[io]archive or should I extend > text_[io]archive by adding serialization of NVPs? > > If, as I think, the right way is to extend text_[io]archive, and more > so if I should actually extend/modify xml_[io]archive, does anyone have > suggestion on how to do that? > > Even better, does anyone have a JSON serializer I could use in a > (*commercial*) project? > > Thanks a lot for your help > > -- > Leo Cacciari > > Aliae nationes servitutem pati possunt. Populi Romani est propria > libertas. > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users

1 0

[serialization] Implementing a JSON archive
by Leo Cacciari 16 Sep '11

16 Sep '11

Hi, for a project I'm working on, I need to be able to send JSON-encoded objects on a network connection. I though that extending the xml_[io]archive classes could do the trick, given that JSON, just like xml, is based on representing an object by a collection of NVPs (name-value pairs). However, I was unable to find an explication on _how_ to extend that class, and I lost myself very quickly when I tried to follow the code in the source. Thus I'm wondering... First, should I actually modify xml_[io]archive or should I extend text_[io]archive by adding serialization of NVPs? If, as I think, the right way is to extend text_[io]archive, and more so if I should actually extend/modify xml_[io]archive, does anyone have suggestion on how to do that? Even better, does anyone have a JSON serializer I could use in a (*commercial*) project? Thanks a lot for your help -- Leo Cacciari Aliae nationes servitutem pati possunt. Populi Romani est propria libertas.

3 2

Abort error with simple Boost regexp
by V A 16 Sep '11

16 Sep '11

Hi, While running the following program using boost 1.26.0, I get an abort error. Any idea why? Thank you. test program ------ int main( int argc, char **argv ) { string yexp = ".*{"; boost::regex expression( yexp.c_str() ); return 0; } // main() Here is the gdb trace: ------ #0 0x618e7ecc in kill () from /usr/lib32/compat/libc.so.4 #1 0x6192c525 in abort () from /usr/lib32/compat/libc.so.4 #2 0x6187d8c8 in __default_terminate () from /home/y/lib/libstdc++.so.2.10 #3 0x6187d8e5 in __terminate () from /home/y/lib/libstdc++.so.2.10 #4 0x6187e1c0 in throw_helper (eh=0x61893c60, pc=0x1002865, my_udata=0xffffdbf0, offset_p=0xffffdbec) from /home/y/lib/libstdc++.so.2.10 #5 0x6187e375 in __throw () from /home/y/lib/libstdc++.so.2.10 #6 0x01002a4b in main (argc=1, argv=0xffffdd24) at testBoost.cc:18

2 1

[test] SIGSEGV using BOOST_CHECK_XXXX from a BOOST_GLOBAL_FIXTURE
by mark Pashley 15 Sep '11

15 Sep '11

Hi all, If any function called by a BOOST_GLOBAL_FIXTURE makes a BOOST_XXXX macro call my test case is terminated with a SIGSEGV. I assume that this is because some part of the boost test framework has not been initialised as the point where by call is made. Is this a known problem or is this intentional behaviour? If this is intentional what should I do instead of calling BOOST_MESSAGE / BOOST_FAIL / BOOST_CHECK (for now I have replaced the last 2 with assert but this is not ideal...). Regards Mark

3 3

[Review] Boost.Endian Review
by joel falcou 15 Sep '11

15 Sep '11

A gentle reminder that the Boost.Endian review is scheduled to end today. Any participant that wish to submit review can do so before tonight Regards

1 0

boost::unordered_map using boost::interprocess::cached_node_allocator compilation failure
by Lenny Maiorani 15 Sep '11

15 Sep '11

Hi Boost-ers, I am trying to create a boost::unordered_map in a boost::interprocess::managed_shared_memory segment. This works fine until I try to change from using boost::interprocess::allocator to boost::interprocess::cached_node_allocator. It seems that the hash_bucket structure is deferring the key size calculation, but the cached_node_allocator needs the size at compilation time. Any ideas on how to make this work? Below is a sample attempt which displays my problem along with the GCC output. Thanks, -Lenny Sample code: #include <boost/interprocess/managed_shared_memory.hpp> #include <boost/interprocess/segment_manager.hpp> #include <boost/interprocess/containers/string.hpp> #include <boost/interprocess/allocators/cached_node_allocator.hpp> #include <boost/unordered_map.hpp> using namespace boost::interprocess; int main () { //Create shared memory. managed_shared_memory segment(create_only, "SharedMem", //segment name 65536); // Define cached node allocator type for char in a shared memory segment. typedef boost::interprocess:: cached_node_allocator<char, managed_shared_memory::segment_manager> cached_node_allocator_t; // Define an interprocess string type which uses the cached node allocator. typedef boost::interprocess:: basic_string<char, std::char_traits<char>, cached_node_allocator_t> shared_string_t; // Get an instance of the allocator. cached_node_allocator_t allocator_instance( segment.get_segment_manager()); // Create an unordered map with Key and Value as interprocess strings, using the default hash and predicate // and use the cached node allocator. boost::unordered_map<shared_string_t, shared_string_t, boost::hash<shared_string_t>, std::equal_to<shared_string_t>, cached_node_allocator_t> my_map_t(allocator_instance); return 0; } GCC output: $ g++ -I/opt/local/include cnasum.cc /opt/local/include/boost/interprocess/allocators/detail/allocator_common.hpp: In instantiation of ‘const size_t boost::interprocess::sizeof_value<boost::unordered_detail::hash_bucket<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >::value’: /opt/local/include/boost/interprocess/allocators/cached_node_allocator.hpp:104: instantiated from ‘boost::interprocess::cached_node_allocator<boost::unordered_detail::hash_bucket<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul>’ /opt/local/include/boost/unordered/detail/fwd.hpp:134: instantiated from ‘boost::unordered_detail::hash_bucket<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >’ /opt/local/include/boost/unordered/detail/fwd.hpp:278: instantiated from ‘boost::unordered_detail::hash_iterator_base<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul>, boost::unordered_detail::ungrouped>’ /opt/local/include/boost/unordered/detail/fwd.hpp:347: instantiated from ‘boost::unordered_detail::hash_buckets<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul>, boost::unordered_detail::ungrouped>’ /opt/local/include/boost/unordered/detail/fwd.hpp:921: instantiated from ‘boost::unordered_detail::types<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::hash<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, std::equal_to<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul>, boost::unordered_detail::map_extractor<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > > >, boost::unordered_detail::ungrouped>’ /opt/local/include/boost/unordered/detail/unique.hpp:125: instantiated from ‘boost::unordered_detail::map<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::hash<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, std::equal_to<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >’ /opt/local/include/boost/unordered/unordered_map.hpp:63: instantiated from ‘boost::unordered_map<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::hash<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, std::equal_to<boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >’ cnasum.cc:35: instantiated from here /opt/local/include/boost/interprocess/allocators/detail/allocator_common.hpp:43: error: invalid application of ‘sizeof’ to incomplete type ‘boost::unordered_detail::hash_bucket<boost::interprocess::cached_node_allocator<std::pair<const boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >, boost::container::basic_string<char, std::char_traits<char>, boost::interprocess::cached_node_allocator<char, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> > >, boost::interprocess::segment_manager<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family, boost::interprocess::offset_ptr<void>, 0ul>, boost::interprocess::iset_index>, 64ul> >’ $

3 3

boost::thread join() and DLL unloading
by Christopher Pisz 15 Sep '11

15 Sep '11

My dll seems to be hanging in the when passed to regsvr32 I debugged through it and it is in deadlock on a boost::thread::join() The call stack tells me: The DLL is unloading The destructor to a global has been called That global contains a boost::thread object, on which join() has been called. (The boost::thread procedure has already exited) join() never returns. I've googled for a few hours and seen people mention something to the effect of "you cannot call join from DllMain" and "while DLL is unloading", but no explanation or alternative. How would I go about fixing this problem? I don't think I can guarentee noone will ever make a global instance of my class....

2 2

Boost.Threads on MSVC++ 9
by Robert Bielik 15 Sep '11

15 Sep '11

Using 1.47.0 I'm trying to use boost.threads on MSVC++ 2008, but run into the "Threading support unavaliable: it has been explicitly disabled with BOOST_DISABLE_THREADS" error. Googling it points to MSVC++ language extensions being disabled. This is not the case for me, language extension are enabled. Ideas? TIA /Rob

2 2

boost 1.47: gcc file dependency generation trips over BOOST_PARAMETER_MAX_ARITY
by Ytsen de Boer 15 Sep '11

15 Sep '11

Hi, To take care of dependencies in my project using boost, I used to invoke gcc with the option -MM. However, since using boost 1.47, this does not work anymore. The precompiler aborts with the message: /usr/local/include/boost-1_47/boost/signals2/signal_type.hpp:29:2: error: #error This header requires BOOST_PARAMETER_MAX_ARITY to be defined as 7 or greater prior to including Boost.Parameter headers Because the macro BOOST_PARAMETER_MAX_ARITY plays no role whatsover in this invocation of gcc, I think that boost should solve their internal problem with the "arity" in some other way. In the mean time I define the macro in my make rules to generate the dependencies, but there it is obviously misplaced (any tips or tricks are welcome here). All the best, Ytsen.

4 5

Fwd: Boost Math error
by Bonee Soibam 15 Sep '11

15 Sep '11

To: boost-users(a)lists.boost.org Date: Wed, 14 Sep 2011 18:44:01 -0400 Subject: Boost Math error Hi , I am a complete newbie with handling Boost errors . i am receiving an error while running a python code which i am working on one of my projects .. i am unable to make way on how to handle this problem .. Can someone put some feedback regarding this .. ____________________________________________________________- Uterminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::math::rounding_error> >' what(): Error in function boost::math::iround<d>(d): Value 3.3559013980333227e+163 can not be represented in the target integer type. Aborted __________________________________________________________________- Please let me know if you ned any more details , Really appreciate it Bonee Soibam

3 2

Concurrent Queue from Boost?
by Jonathon 15 Sep '11

15 Sep '11

Hi, Is there an implementation of a concurrent, lock-free, queue? I remember reading that there was an implementation, but I can't find the e-mail :) Thanks, J

4 4

boost version of qt signals (including cross-thread event generation)
by Daniel Oberhoff 15 Sep '11

15 Sep '11

Hi, I am currently building a software component that does stream processing in a dataflow like scheme (i.e. data flows through a network of algorithm blocks, much like in simulink, if you know matlab). I am currently implementing it all using qt signals and slots, since this allows me to push parts off to different threads, and qt magically handles the event generation. i.e. when I connect across threads instead of directly invoking the slot qt will generate an event in the receivers thread's eventloop (such eventloops are automatically generated for all QThreads). Now I am a bit frutrated by the hackishnes of the qt preprocessor (moc) that implements the signal/slot magic, as it does not compute with templates and typedefs, making my code unneccesarily verbose. So I was wondering how easy/hard it would be to implement such a thing with boost? I nknow there is signals2, but that does not implement the message passing scheme I want, instead it just savely calls slot directly. In terms of event-loops there is boost asio, right? Is there a sane way to combine these? It would be great as I think this kind of scheme can be used in many places. Best Daniel

3 2

[Context] Context library status?
by Nat Linden 14 Sep '11

14 Sep '11

http://lists.boost.org/boost-announce/2011/05/0310.php I'd like to ask Oliver about the current status of the Context library. I just spent a couple of weeks grappling with a mystery bug that was ultimately due to exceeding the stack size we'd allocated for a Boost.Coroutine. It made me think of the Boost.Context promise that each stack is protected by a read-only guard page, so that stack overflow is immediately and unambiguously caught. Once the Boost.Context API has stabilized, it would probably be worth it for me to replace the present Boost.Coroutine underpinnings with Boost.Context. I do realize that Oliver (and probably others) have Context-based high-level libraries in the pipeline, but at least for us, for now, Coroutine+Context would provide an immediate benefit.

2 1

boost::xpressive : Get thousand separator as double
by Jens Saathoff 14 Sep '11

14 Sep '11

Hi! I'm playing a bit with boost::xpressive and have no clue how to get a 100,000 (comma as separator) to a double as 1000000.00 or 250,000.10 as a double 250000.10 or 12,00 as double 12.00 or 1,200,500.00 as double 1200500.00. I'm working with xpressive since a day. What's the regex for that? And how can i use it in xpressive-grammar as a nested regex? Example subject: "I payed 100,200.50 Dollar" Example Regex on subject: 'I payed' >> (s1=getdoubleregex) >> ' Dollar' Is it possible to do it like that? Set return-value/type in a regex? Thank you very much!

2 8

begin (cout) or boost::copy to cout
by Krzysztof Żelechowski 14 Sep '11

14 Sep '11

== The Problem == Boost.Range defines boost:: begin to give you the iterator to every possible container — except ostream. == Solution 1 == === Implementation === I have the following function for you to add to Boost.Range: template < class P_I, class P_C, class P_T > std:: ostream_iterator < typename boost:: iterator_value < P_I >:: type, P_C, P_T > begin (std:: basic_ostream < P_C, P_T > &p_s, P_I const &, P_C const p_p [] = NULL) { return std:: ostream_iterator < typename boost:: iterator_value < P_I >:: type, P_C, P_T > (p_s, p_p); } === Application === to be used in the following way: void foo (std:: vector < int > const &v) { boost:: copy (v, boost:: begin (std:: cout, boost:: begin (v), " "); } This function eliminats the need of passing explicit template parameters to std:: ostream_iterator, which makes the code fragile and hard to read. == Solution 2 == === Motivation === Since an output stream iterator is not useful except for copying to an output stream, a further simplification is also possible: === Implementation === template < class P_R, class P_C, class P_T > std:: basic_ostream < P_C, P_T > &copy (P_R const &p_r, std:: basic_ostream < P_C, P_T > &p_s, P_C const p_p [] = NULL) { copy (p_r, std:: ostream_iterator < typename boost:: range_value < P_R >:: type, P_C, P_T > (p_s, p_p)); return p_s; } === Application === and it enables the following invocation: void foo (std:: vector < int > const &v) { boost:: copy (v, std:: cout, " "); } Please consider. Chris

3 4

"weak" binding to member?
by John M. Dlugosz 14 Sep '11

14 Sep '11

I know that 'bind' (now in std::tr1) will bind pointers to member functions to smart pointers. But is there a simple way to bind to a "weak" pointer, such that the attempted call will realize the smart pointer and if successful perform the call, or if unsuccessful just not call anything without complaint? (In this case, it appears that the return is void) —John

2 6

[Boost.Polygon] support for polygons with holes
by Björn Piltz 14 Sep '11

14 Sep '11

I'm playing around with Boost.Polygon and I'm wondering what functionality is supported for the polygon_with_holes concept. Specifically the boolean operators. For example, can I create a polygon_set with polygon_with_holes. I would like to punch a hole in a polygon and get a polygon with a hole as supposed to a key holed contour. Similarily, when combining the following rectangles: p += rectangle_data<int>(0, 0, 100, 10); p += rectangle_data<int>(90, 0, 100, 100); p += rectangle_data<int>(0, 90, 100, 100); p += rectangle_data<int>(0, 0, 10, 100); I would like to end up with +-----+ | | | +-+ | | | | | | +-+ | | | +-----+ as opposed to +-----+ | | | +-+ | | | | | | +-+ | | | | +---+-+

4 9

[type_traits][function_traits] generic way of obtaining argument of *both* a function and function object
by alfC 14 Sep '11

14 Sep '11

Hi, Is there a uniform way to obtain the argument type of function object and of a function at the same time. For example: double fun(int a){ return ... ;} struct A{ double operator()(int a){ return ...;} typedef int argument_type; // or something like this (if needed) }; template<class F> print_argument_type(F f){ std::cout << typeid( argument_of<F>::type // or something like this ?? ).name() << std::endl; } A a; print_argument(fun); //should print "int" print_argument(a); //should print "int" Of course I am asking for something that at least works on objects in which operator() is not overloaded. For functions we have function_traits< ... >::arg1_type (and other MPL variants) but I can not find a generic solution that also works for objects. In other words I need something like boost/std::result_of but for the argument type; if this is not possible in general because of language limitations (e.g. because operator() can be overloaded) I am willing to accept any convention from out there that works both for functions and funciton objects. Just wanted to know what boost can say about this problem. Maybe something that looks into the arguments of the member-function A::operator() via type_traits in case A is a class? Thanks, Alfredo

2 1

Boost MSM - Ways to send info out from state machine to outside world
by gauravk 13 Sep '11

13 Sep '11

Hi, I wanted to know what are different ways to send info from state machine to outside world. I am planning to use MSM in my project to represent connection between local computer and remote computer. This connection will be used as a channel to send data over to remote device. There can be >1 channels existing between local computer and the remote device. There will be a controller sitting at local computer monitoring all these channels. The data will be sent over connection that is idle/free at that point of time. Whenever the connection, i.e. FSM, is done sending the data, it will let the controller (which resides outside of the FSM) know that it is done sending the data and the controller will then send next lot of data over that connection. There can be 2 ways of achieving this: 1. Controller polling all the connections and knowing what "state" the FSM is in.(In this case, the outer world will need to know the current state of the state machine) 2. The FSM will proactively let the controller know that it is done with sending data. (In this case the FSM will have to send data to outside world). I would like to know about ways to implement both the cases (i.e knowing status/current state of the FSM and sending info from FSM). I would also like to know what are different ways to interact with (both to and from) FSM in general, apart from sending events. Thanks! -- View this message in context: http://boost.2283326.n4.nabble.com/Boost-MSM-Ways-to-send-info-out-from-sta… Sent from the Boost - Users mailing list archive at Nabble.com.

2 8

array alignment in ublas matrices
by petros 13 Sep '11

13 Sep '11

Hi, I am using the ublas matrices with mkl. The documentation of mkl suggests/requires that allocated arrays are aligned on 16 byte boundaries. The matrix structures within ublas delegate the memory management in the std allocator which at the very end reduces to new. I know that one way to address this is write my own allocator for the unbounded_array that lies on the basis of the storage structures. However, this is an error-prone job and it is suggested that this is avoided. Any other solutions? – hopefully more straightforward ? Thank you in advance for your help, Petros ps: using visual studio 2010 on winn7/visa 64 bit and mkl 10.3.

2 2

[serialization] yaml archive compilation
by alfC 12 Sep '11

12 Sep '11

Hi, did any body succeed in compiling the YAML component of Boost.Serialization located in https://github.com/boost-vault/serialization ? I really don't understand what should I do with the yaml_oarchive.cpp yaml_iarchive.cpp, etc, contained in the src directory. The source don't have makefiles, should I put those in the boost source tree? Thanks, Alfredo

1 0

LINK Error while building PBGL example breadth_first_search.cpp
by 余韬 12 Sep '11

12 Sep '11

Hi, I am trying to learn PBGL. I am using VS2008 on Win 7. I had built and installed open mpi 1.4.3, HPC Pack 2008 SDK, and Boost library 1.46.1 with "bjam --with-mpi --with-graph_parallel". I had set include and library directory for the above 3 libraries in VS2008. The additional dependency set for the project is "libboost_*mpi*-vc90-mt-gd.lib libboost_*serialization*-vc90-mt-gd.lib libboost_wserialization-vc90-mt-gd.lib libboost_graph-vc90-mt-gd.lib libboost_*graph_parallel*-vc90-mt-gd.lib libboost_system-vc90-mt-gd.lib libmpi_cxxd.lib libmpid.lib libopen-pald.lib libopen-rted.lib msmpi.lib" Here are the major references I had referred which helped to reduce errors significantly: http://terboven.wordpress.com/2008/09/09/building-and-using-boostmpi-on-win… http://lists.boost.org/boost-users/2009/11/54042.php However, while compiling D:\Development\boost_1_46_1\libs\graph_parallel\example\breadth_first_search.cpp on my machine, I still got the following 4 link errors: Error 4 error LNK2019: unresolved external symbol "*private: struct ompi_datatype_t * __thiscall boost::mpi::detail::mpi_datatype_map::get(class type_info const *)*" breadth_first_search.obj Error 3 error LNK2019: unresolved external symbol "*private: void __thiscall boost::mpi::detail::mpi_datatype_map::set(class type_info const *,struct ompi_datatype_t *)*" breadth_first_search.obj Error 2 error LNK2019: unresolved external symbol "*public: __thiscall boost::mpi::communicator::operator struct ompi_communicator_t *(void)const*" breadth_first_search.obj Error 1 error LNK2019: unresolved external symbol "void __cdecl boost::detail::bfs_helper<class boost::adjacency_list<struct boost::vecS,struct boost::distributedS<class boost::graph::distributed::mpi_process_group,struct boost::vecS,struct boost::defaultS>......" breadth_first_search.obj Am I missing something here? Thanks, Tao Yu http://about.me/Tao_Yu

1 1

graph documentation dead link
by Benjamin Sobotta 12 Sep '11

12 Sep '11

Hello, I'm currently reading about the graph library, more specifically about the shortest path problem with resource constraints, and found that the link to the paper Irnich, S.; Desaulniers, G. (2005): Shortest Path Problems with Resource Constraints in: Desaulniers, G.; Desrosiers, J.; Solomon, M. (eds.) (2005): Column Generation Springer, New York, pp. 33–65 is broken. I found a new link to the paper: http://logistik.bwl.uni-mainz.de/Dateien/or_2004-01.pdf Cheers, Ben PS: The link is in .../doc/libs/1_47_0/libs/graph/doc/r_c_shortest_paths.html under "Introduction and Problem Description"

2 1

thread running many times
by Kraus Philipp 12 Sep '11

12 Sep '11

Hello, I create a thread group and run the group with join_all(). My code shows like: for(i=0; i < runs; ++i) { threadgoup.join_all(); do something with the results } So I run the thread group n times. Is this the correct way or can I call join_all only once on the group? Thanks PHil

3 8

[asio] serial_port::async_read_some() with native COM ports on WIN32
by Running Razor 12 Sep '11

12 Sep '11

I use serial_port::async_read_some() to read data from serial interface on windows. Using virtual com ports (FTDI, SiLabs) everything wents as expected. But on native COM ports the completion handler is not called until the buffer (passed to async_read_some) is completely filled. I use "plain" communication without hardware handshake: ... typedef serial_port_base ser; mDevice.set_option( ser::baud_rate ( baud ) ); mDevice.set_option( ser::flow_control ( ser::flow_control::none ) ); mDevice.set_option( ser::parity ( ser::parity::none ) ); mDevice.set_option( ser::stop_bits ( ser::stop_bits::one ) ); mDevice.set_option( ser::character_size( 8 ) ); ... Do I miss something or is this a bug? tested on boost_1_38_0 and boost_1_46_1

1 0

boost thread (non-blocking) communication
by Jack Bryan 11 Sep '11

11 Sep '11

Hi, I am trying to do data-exchange communication among boost::threads. Are there asynchronous (non-blocking) communication APIs in boost ? For example, non_block_send( receiver_address, data_buffer, data_volume, data_tag , send_status ); non_block_recv( sender_address, data_buffer, data_volume, data_tag , recv_status ); if (recv_status == TRUE) getData(data_buffer) ; else wait; Any help is really appreciated. Thanks

4 4

Compile errors using boost 4.7.4 and Intel ICC x64 on Debian
by Bill Moo 11 Sep '11

11 Sep '11

Hello List. The attached file contains the errors I get when I attempt to compile my utilities library using Boost 1.47.0 with the Intel Compiler v12.1.0 on Debian Squeeze v6.0.2. (My IDE is Qt Creator v2.3.0 using v4.7.4 (x64) SDK) This is my first attempt at doing this under Linux as the utilities library (dll) compile as is in Windows. So I would appreciate your thoughts on this as I can't continue the migration of the other projects until I get this library working. Thank you. -- Bill

1 0

dijkstra_shortest_paths between sets of nodes (between polygons on a grid)
by Stuck Developer 10 Sep '11

10 Sep '11

This ought to be a classic problem but I haven't found a solution yet... Conceputally, I'm trying to find the shortest paths between all polygons within a maximum weighted distance over a grid of friction weights (as well as the total weighted distance of each of these shortest paths). The grid with all the weights (a "friction" value representing the weight to move over that particular grid cell) is currently used to create a network with one vertex per grid cell and edges to its immediate eight neighbours (in the cardinal and diagonal directions). The weight of each edge is calculated to the average weight of the vertex and its neigbours in the four cardinal directions and multiplied by sqrt(2) in the diagonal directions to compensate for the longer euclidean distance. Conceptually again, on this grid, there are a bunch of polygons. These are then made up ofcontiguous groups of vertices. Each polygon could thus be considered a set (or a component) of vertices with a unique id for each polygon. The problem now is to find the shortest path over the weighted grid between the edges of all polygons within a maximum weighted distance from each other. NOTE that the shortest path between two polygons should be able to pass through the weighted grid cells of other polygons along the way when these other polygons are not considered being source or target "vertex sets". I first tried to solve this by looping through all of the polygons and finding the shortest path between some representative vertex (e.g. the centroid grid cell) inside a source polygon to a representative vertex within each possible target polygon. I did this by setting all of the grid cell weights to zero within each of the two polygons, running the dijkstra_shortest_paths between their representative vertices and then resetting the weights within these two polygons before solving it for another pair of polygons. This actually works but the search goes bezerk within the polygons where all the edges have a cost of zero, and if these polygons are big enough, I run out of memory (I guess the shortest path becomes too long...). I'm thinking this should be possible to solve by instead initializing all of the vertices within each source polygon to "discovered" (i.e. black) somehow and initializing the priority queue and the cost in some corresponding manner. I just don't know how. Then there is the question of knowing when the shortest path to the target polygon has been reached... And thirdly if it would be possible to stop the search when a maximum weighted distance has been reached. Any smart solutions to this problem?

2 1

Re: [Boost-users] [bind] Dereferencing placeholder argument
by Ivan Le Lann 09 Sep '11

09 Sep '11

----- "Szymon Gatner" <szymon.gatner(a)gmail.com> a écrit : > 2011/9/9 Nat Linden <nat(a)lindenlab.com>: > > On Fri, Sep 9, 2011 at 10:04 AM, Ivan Le Lann <ivan.lelann(a)free.fr> > wrote: > > >> Have you tried *_1 ? > > > > I think that works with boost::lambda::bind and boost::lambda::_1 > > (also, presumably, the corresponding constructs in Phoenix) but not > > with plain boost::bind. > > Indeed I tried that - getting invalid indirection error. Some time ago I offered a patch to add arithmetical operator support to Boost.Bind and was answered : Use Lambda or Phoenix. If you want to tweak Boost.Bind, which I would not encourage, maybe this could help : http://boost.2283326.n4.nabble.com/Bind-Function-arithmetic-sample-impl-ins… As said, it is for arithmetical operators but might be adapted to your need. Regards, Ivan

1 0

Re: [Boost-users] [bind] Dereferencing placeholder argument
by Ivan Le Lann 09 Sep '11

09 Sep '11

----- "Szymon Gatner" <szymon.gatner(a)gmail.com> a écrit : > Hi, > > Is there a way of automatic placeholder argument dereferencing when > using bind()? I mean: > > struct SomePredicate > { > bool operator()(int num, const Foo& foo) const > { > return SomeTestOnFoo(num, foo); > } > } > > std::vector<Foo*> foos; > > // line below gives compilation error because second argument passed > // to functor is Foo* and not Foo. > > std::for_each(foos.begin(), foos.end(), bind(SomePredicate(), 123, > _1); >From http://www.boost.org/doc/libs/1_47_0/doc/html/lambda/le_in_details.html#id2… (section "Sizeof and typeid") for_each(a.begin(), a.end(), cout << bind(&type_info::name, ll_typeid(*_1))); Have you tried *_1 ? Regards, Ivan

3 2

memory lost using cyclic pointers (shared_ptr)
by Peng Yu 09 Sep '11

09 Sep '11

Hi, I think that it is expected that shared_ptr cannot handle points that have cyclic references. In the following example, "a" points to "b" and "b" points to "a". There is a memory leak. I then modified it to remove the dependence using bare pointers, then the leak is resolved. But this is not a very satisfactory solution, as the programmer has to know whether to use bare point or shared_ptr. For very complexity program, it may not be possible to figure out it correctly. Does anybody know what is the best strategy for handing cyclic pointers? ~/linux/test/cpp/library/std/tr1/shared_ptr/loop$ cat main.cpp #include <tr1/memory> #include <iostream> struct B; struct A { std::tr1::shared_ptr<B> p; void print() { std::cout << "A" << std::endl; } }; struct B { std::tr1::shared_ptr<A> p; void print() { std::cout << "B" << std::endl; } }; int main () { std::tr1::shared_ptr<A> a(new A); std::tr1::shared_ptr<B> b(new B); a->p=b; b->p=a; a->p->print(); b->p->print(); } ~/linux/test/cpp/library/std/tr1/shared_ptr/loop$ valgrind ./main.exe ==75090== Memcheck, a memory error detector ==75090== Copyright (C) 2002-2010, and GNU GPL'd, by Julian Seward et al. ==75090== Using Valgrind-3.6.1 and LibVEX; rerun with -h for copyright info ==75090== Command: ./main.exe ==75090== --75090-- ./main.exe: --75090-- dSYM directory is missing; consider using --dsymutil=yes B A ==75090== ==75090== HEAP SUMMARY: ==75090== in use at exit: 4,280 bytes in 6 blocks ==75090== total heap usage: 6 allocs, 0 frees, 4,280 bytes allocated ==75090== ==75090== LEAK SUMMARY: ==75090== definitely lost: 16 bytes in 1 blocks ==75090== indirectly lost: 80 bytes in 3 blocks ==75090== possibly lost: 0 bytes in 0 blocks ==75090== still reachable: 4,184 bytes in 2 blocks ==75090== suppressed: 0 bytes in 0 blocks ==75090== Rerun with --leak-check=full to see details of leaked memory ==75090== ==75090== For counts of detected and suppressed errors, rerun with: -v ==75090== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0) #removing cyclic reference by using bare pointer. ~/linux/test/cpp/library/std/tr1/shared_ptr/loop$ cat main.cpp #include <tr1/memory> #include <iostream> struct B; struct A { std::tr1::shared_ptr<B> p; void print() { std::cout << "A" << std::endl; } }; struct B { std::tr1::shared_ptr<A> p; void print() { std::cout << "B" << std::endl; } }; int main () { std::tr1::shared_ptr<A> a(new A); std::tr1::shared_ptr<B> b(new B); a->p=b; b->p=a; a->p->print(); b->p->print(); } ~/linux/test/cpp/library/std/tr1/shared_ptr/loop$ vim main.cpp ~/linux/test/cpp/library/std/tr1/shared_ptr/loop$ make g++ -o main.exe main.cpp ~/linux/test/cpp/library/std/tr1/shared_ptr/loop$ valgrind main.exe valgrind: main.exe: command not found ~/linux/test/cpp/library/std/tr1/shared_ptr/loop$ valgrind ./main.exe ==75167== Memcheck, a memory error detector ==75167== Copyright (C) 2002-2010, and GNU GPL'd, by Julian Seward et al. ==75167== Using Valgrind-3.6.1 and LibVEX; rerun with -h for copyright info ==75167== Command: ./main.exe ==75167== --75167-- ./main.exe: --75167-- dSYM directory is missing; consider using --dsymutil=yes B A ==75167== ==75167== HEAP SUMMARY: ==75167== in use at exit: 4,184 bytes in 2 blocks ==75167== total heap usage: 6 allocs, 4 frees, 4,272 bytes allocated ==75167== ==75167== LEAK SUMMARY: ==75167== definitely lost: 0 bytes in 0 blocks ==75167== indirectly lost: 0 bytes in 0 blocks ==75167== possibly lost: 0 bytes in 0 blocks ==75167== still reachable: 4,184 bytes in 2 blocks ==75167== suppressed: 0 bytes in 0 blocks ==75167== Rerun with --leak-check=full to see details of leaked memory ==75167== ==75167== For counts of detected and suppressed errors, rerun with: -v ==75167== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0) -- Regards, Peng

4 3

[bind] Dereferencing placeholder argument
by Szymon Gatner 09 Sep '11

09 Sep '11

Hi, Is there a way of automatic placeholder argument dereferencing when using bind()? I mean: struct SomePredicate { bool operator()(int num, const Foo& foo) const { return SomeTestOnFoo(num, foo); } } std::vector<Foo*> foos; // line below gives compilation error because second argument passed // to functor is Foo* and not Foo. std::for_each(foos.begin(), foos.end(), bind(SomePredicate(), 123, _1); I don't want to use indirect() adaptor from boost.range because I want final output range to still have Foo* as value_type so that it can still be copied to another std::vector<Foo*> etc. So: is there a way of telling bind() that is should dereference a placeholder argument before passing it to underlying bound functor? Regards, Simon -- Szymon Gatner The Lordz Games Studio www.thelordzgamesstudio.com

1 0

[container] Initialization from transformed_range compilation error
by Szymon Gatner 09 Sep '11

09 Sep '11

Hi, snipped below gives this error in VS 2008 SP1: Error 1 error C2664: 'void boost::container::vector<T>::priv_range_insert<InIt>(Object **,FwdIt,FwdIt,std::forward_iterator_tag)' : cannot convert parameter 4 from 'boost::detail::iterator_category_with_traversal<Category,Traversal>' to 'std::forward_iterator_tag' c:\devel\boost_1_47_0\boost\container\vector.hpp 1908 copy_range code: #include <boost/container/vector.hpp> #include <boost/range/adaptor/transformed.hpp> #include <functional> class Object; struct DecodeID : public std::unary_function<int, Object*> { Object* operator() (int id) const { return 0; } }; int main() { using namespace boost; using namespace boost::container; using namespace boost::range; vector<int> ids; vector<Object*> objects = copy_range<vector<Object*> >(adaptors::transform(ids, DecodeID())); } Am I missing something obvious here? Regards, Szymon P.S. full build log: 1>------ Build started: Project: copy_range, Configuration: Debug Win32 ------ 1>Compiling... 1>main.cpp 1>c:\devel\boost_1_47_0\boost\container\vector.hpp(1908) : error C2664: 'void boost::container::vector<T>::priv_range_insert<InIt>(Object **,FwdIt,FwdIt,std::forward_iterator_tag)' : cannot convert parameter 4 from 'boost::detail::iterator_category_with_traversal<Category,Traversal>' to 'std::forward_iterator_tag' 1> with 1> [ 1> T=Object *, 1> InIt=boost::transform_iterator<DecodeID,boost::container::containers_detail::vector_iterator<int *>>, 1> FwdIt=boost::transform_iterator<DecodeID,boost::container::containers_detail::vector_iterator<int *>> 1> ] 1> and 1> [ 1> Category=std::input_iterator_tag, 1> Traversal=boost::random_access_traversal_tag 1> ] 1> No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called 1> c:\devel\boost_1_47_0\boost\container\vector.hpp(1093) : see reference to function template instantiation 'void boost::container::vector<T>::priv_insert_dispatch<InIt>(boost::container::containers_detail::vector_const_iterator<Pointer>,InIt,InIt,boost::container::containers_detail::false_)' being compiled 1> with 1> [ 1> T=Object *, 1> InIt=boost::transform_iterator<DecodeID,boost::container::containers_detail::vector_iterator<int *>>, 1> Pointer=Object ** 1> ] 1> c:\devel\boost_1_47_0\boost\container\vector.hpp(1761) : see reference to function template instantiation 'void boost::container::vector<T>::insert<InIt>(boost::container::containers_detail::vector_const_iterator<Pointer>,InIt,InIt)' being compiled 1> with 1> [ 1> T=Object *, 1> InIt=boost::transform_iterator<DecodeID,boost::container::containers_detail::vector_iterator<int *>>, 1> Pointer=Object ** 1> ] 1> c:\devel\boost_1_47_0\boost\container\vector.hpp(1895) : see reference to function template instantiation 'void boost::container::vector<T>::priv_assign_aux<InIt>(InIt,InIt,std::input_iterator_tag)' being compiled 1> with 1> [ 1> T=Object *, 1> InIt=boost::transform_iterator<DecodeID,boost::container::containers_detail::vector_iterator<int *>> 1> ] 1> c:\devel\boost_1_47_0\boost\container\vector.hpp(867) : see reference to function template instantiation 'void boost::container::vector<T>::priv_assign_dispatch<InIt>(InIt,InIt,boost::container::containers_detail::false_)' being compiled 1> with 1> [ 1> T=Object *, 1> InIt=boost::transform_iterator<DecodeID,boost::container::containers_detail::vector_iterator<int *>> 1> ] 1> c:\devel\boost_1_47_0\boost\container\vector.hpp(487) : see reference to function template instantiation 'void boost::container::vector<T>::assign<InIt>(InIt,InIt)' being compiled 1> with 1> [ 1> T=Object *, 1> InIt=boost::transform_iterator<DecodeID,boost::container::containers_detail::vector_iterator<int *>> 1> ] 1> c:\devel\boost_1_47_0\boost\range\iterator_range_core.hpp(640) : see reference to function template instantiation 'boost::container::vector<T>::vector<boost::transform_iterator<UnaryFunc,Iterator>>(InIt,InIt,const std::allocator<_Ty> &)' being compiled 1> with 1> [ 1> T=Object *, 1> UnaryFunc=DecodeID, 1> Iterator=boost::container::containers_detail::vector_iterator<int *>, 1> InIt=boost::transform_iterator<DecodeID,boost::container::containers_detail::vector_iterator<int *>>, 1> _Ty=Object * 1> ] 1> c:\users\bravo\documents\visual studio 2008\projects\copy_range\copy_range\main.cpp(23) : see reference to function template instantiation 'SeqT boost::copy_range<boost::container::vector<T>,boost::range_detail::transformed_range<F,R>>(const Range &)' being compiled 1> with 1> [ 1> SeqT=boost::container::vector<Object *>, 1> T=Object *, 1> F=DecodeID, 1> R=boost::container::vector<int>, 1> Range=boost::range_detail::transformed_range<DecodeID,boost::container::vector<int>> 1> ] 1>Build log was saved at "file://c:\Users\bravo\Documents\Visual Studio 2008\Projects\copy_range\copy_range\Debug\BuildLog.htm" 1>copy_range - 1 error(s), 0 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== -- Szymon Gatner The Lordz Games Studio www.thelordzgamesstudio.com

3 22

asio::io_service as a thread-pool executor
by aiooua 08 Sep '11

08 Sep '11

I'm trying to use boost::asio::io_service as a thread pool executor. Here's my attempt: ---- using std::vector; using boost::bind; using boost::thread; using boost::shared_ptr; using boost::asio::io_service; class executor { public: executor(size_t n): service_(n), work_(service_) { for (size_t i = 0; i < n; i++) { shared_ptr<thread> worker(new thread(bind(&io_service::run, &service_))); pool_.push_back(worker); } } ~executor() { service_.stop(); for (auto i = pool_.begin(); i != pool_.end(); ++i) { (*i)->join(); } } template<typename F> void submit(F task) { service_.post(task); } private: io_service service_; io_service::work work_; vector<shared_ptr<thread> > pool_; }; void work() {} void other_work(const char *c) {} struct functor_work { void operator()() {} }; auto lambda = [] {}; int main() { executor e(4); e.submit(work); e.submit(boost::bind(other_work, "input")); e.submit(functor_work()); e.submit(lambda); } ---- Is this usage correct or am I missing anything here? The bit I'm not sure about in particular is this: Is it guaranteed that the io_service::run will wait for the completion of the posted jobs (via io_service::post) after I have called io_service::stop? In other words, do I have to explicitly ensure that my executor instance lives at least as long as the last submitted job has finished? Or can I assume that io_service::run will only return after all its posted jobs have had a chance to finish? Thanks!

1 0

[Units] defining a derived dimension
by Michael Powell 08 Sep '11

08 Sep '11

I want to define a dimension stroke_rate, or flow_rate, for that matter. Not too out of the ordinary for our application. So I am starting with something like this for my dimensions. #include <boost/units/derived_dimension.hpp> #include <boost/units/physical_dimensions/length.hpp> #include <boost/units/physical_dimensions/time.hpp> typedef boost::units::derived_dimension<boost::units::dimensionless_type,1,boost::units::time_base_dimension,-1>::type stroke_rate_dimension; typedef boost::units::derived_dimension<boost::units::length_dimension,3,boost::units::time_dimension,-1>::type flow_rate_dimension; typedef boost::units::unit<ourns::units::stroke_rate_dimension,boost::units::si::system> stroke_rate; typedef boost::units::unit<ourns::units::flow_rate_dimension,boost::units::si::system> flow_rate; However, I am receiving compiler errors when I try and include the units, Error 1 error C2039: 'value' : is not a member of 'boost::units::detail::dimension_list_tag' C:\Source\Simulations\tools\boost-msvc90-pro\boost\mpl\aux_\preprocessed\plain\less.hpp 20 CS.Calculations.Managed Error 2 error C2065: 'value' : undeclared identifier C:\Source\Simulations\tools\boost-msvc90-pro\boost\mpl\aux_\preprocessed\plain\less.hpp 21 CS.Calculations.Managed Error 3 error C2039: 'value' : is not a member of 'boost::units::detail::dimension_list_tag' C:\Source\Simulations\tools\boost-msvc90-pro\boost\mpl\aux_\preprocessed\plain\less.hpp 21 CS.Calculations.Managed Error 4 error C2065: 'value' : undeclared identifier C:\Source\Simulations\tools\boost-msvc90-pro\boost\mpl\aux_\preprocessed\plain\less.hpp 22 CS.Calculations.Managed And so on along these lines. What am I doing wrong with the units and/or dimensions? This is quite similar to energy_density_dimension, for example. typedef derived_dimension<length_base_dimension,-1,mass_base_dimension,1,time_base_dimension,-2>::type energy_density_dimension; However, I am failing to see any appreciable difference. Any thoughts? Thanks, Michael

2 4

units length operator * / area
by Michael Powell 08 Sep '11

08 Sep '11

Units users, How do I define an operator* which takes a quantity<length>,quantity<length> and returns a quantity<area>? This doesn't seem to be defined in the boost::units, which somewhat surprises me. How do we make something like that part of the core definition? Thanks, Michael

1 1

Unicode support in boost?
by code 08 Sep '11

08 Sep '11

Hi, Can someone tell me how much Boost supports Uincode? Thank you

5 10

Wave Linker Error
by Alexander Feldman 08 Sep '11

08 Sep '11

Gentlemen, I'm getting the following linker error: /tmp/ccTiqxQC.o: In function `boost::wave::cpplexer::lex_input_interface<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >* boost::wave::cpplexer::lex_input_interface_generator<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >::new_lexer<boost::spirit::classic::position_iterator<boost::spirit::basic_istream_iterator<char, std::char_traits<char> >, boost::spirit::classic::file_position_base<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::spirit::classic::nil_t> >(boost::spirit::classic::position_iterator<boost::spirit::basic_istream_iterator<char, std::char_traits<char> >, boost::spirit::classic::file_position_base<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::spirit::classic::nil_t> const&, boost::spirit::classic::position_iterator<boost::spirit::basic_istream_iterator<char, std::char_traits<char> >, boost::spirit::classic::file_position_base<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::spirit::classic::nil_t> const&, boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > const&, boost::wave::language_support)': wave+spirit.cpp:(.text._ZN5boost4wave8cpplexer29lex_input_interface_generatorINS1_9lex_tokenINS0_4util13file_positionINS4_11flex_stringIcSt11char_traitsIcESaIcENS4_9CowStringINS4_22AllocatorStringStorageIcS9_EEPcEEEEEEEEE9new_lexerINS_6spirit7classic17position_iteratorINSK_22basic_istream_iteratorIcS8_EENSL_18file_position_baseISsEENSL_5nil_tEEEEEPNS1_19lex_input_interfaceISH_EERKT_SY_RKSG_NS0_16language_supportE[boost::wave::cpplexer::lex_input_interface<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >* boost::wave::cpplexer::lex_input_interface_generator<boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >::new_lexer<boost::spirit::classic::position_iterator<boost::spirit::basic_istream_iterator<char, std::char_traits<char> >, boost::spirit::classic::file_position_base<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::spirit::classic::nil_t> >(boost::spirit::classic::position_iterator<boost::spirit::basic_istream_iterator<char, std::char_traits<char> >, boost::spirit::classic::file_position_base<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::spirit::classic::nil_t> const&, boost::spirit::classic::position_iterator<boost::spirit::basic_istream_iterator<char, std::char_traits<char> >, boost::spirit::classic::file_position_base<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::spirit::classic::nil_t> const&, boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > const&, boost::wave::language_support)]+0x13): undefined reference to `boost::wave::cpplexer::new_lexer_gen<boost::spirit::classic::position_iterator<boost::spirit::basic_istream_iterator<char, std::char_traits<char> >, boost::spirit::classic::file_position_base<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::spirit::classic::nil_t>, boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > >, boost::wave::cpplexer::lex_token<boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >::new_lexer(boost::spirit::classic::position_iterator<boost::spirit::basic_istream_iterator<char, std::char_traits<char> >, boost::spirit::classic::file_position_base<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::spirit::classic::nil_t> const&, boost::spirit::classic::position_iterator<boost::spirit::basic_istream_iterator<char, std::char_traits<char> >, boost::spirit::classic::file_position_base<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, boost::spirit::classic::nil_t> const&, boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > const&, boost::wave::language_support)' collect2: ld returned 1 exit status -------------------------- Trying to link: std::ifstream instream(argv[1]); std::string instring; if (!instream.is_open()) { std::cerr << "Could not open input file: " << argv[1] << std::endl; return -2; } instream.unsetf(std::ios::skipws); typedef boost::spirit::classic::position_iterator<boost::spirit::istream_iterator> pos_iterator; boost::spirit::istream_iterator begin1(instream); boost::spirit::istream_iterator end1; pos_iterator begin(begin1, end1, argv[1]); pos_iterator end; typedef boost::wave::cpplexer::lex_token<> token_type; typedef boost::wave::cpplexer::lex_iterator<token_type> lex_iterator_type; typedef boost::wave::context<pos_iterator, lex_iterator_type> context_type; context_type ctx(begin, end, argv[1]); context_type::iterator_type preprocessedInputBegin = ctx.begin(); context_type::iterator_type preprocessedInputEnd = ctx.end(); --------------- Any ideas what am I missing? Thanks, -- Alex

2 2

[Serialization]Serialization of pointer to pointers
by Kangkook Jee 08 Sep '11

08 Sep '11

Hi, all I'm trying to use boost library for serialization of my program which contains many custom class definitions. However, I can't figure out how to handle a class member which is *pointer to pointers* such as 'a' from the following code snippet. class B { A** a; friend class boost::serialization::access; … template<class Archive> void serialize(Archive &ar, const unsigned int version) { ar & a: …. Above code fails to be compiled with the following error message. … /usr/include/boost/archive/detail/oserializer.hpp:148:5: instantiated from ‘void boost::archive::detail::oserializer<Archive, T>::save_object_data(boost::archive::detail::basic_oarchive&, const void*) const [with Archive = boost::archive::text_oarchive, T = A*]’ serial0.cpp:118:1: instantiated from here /usr/include/boost/serialization/access.hpp:118:9: error: request for member ‘serialize’ in ‘t’, which is of non-class type ‘A*’ Do we have a typical way to handle a such case? I spend some time to find a solution from the web and tutorials but I couldn't. I'm new to the boost library and your helps will be greatly appreciated. Thanks, Kangkook

2 1

Re: [Boost-users] [!! SPAM] Wave Preprocessor without Using a Lexer
by Hartmut Kaiser 08 Sep '11

08 Sep '11

> Does anybody know how to use the wave preprocessor *without* using the cpp > lexer? That does not work. The Wave parser depends on getting tokenized input. This is by design and probably different from any other preprocessor. Those are normally implemented on the character level. Wave is not, it's a tokenizing preprocessor. Regards Hartmut --------------- http://boost-spirit.com

1 0

Re: [Boost-users] Unicode support in boost?
by code 07 Sep '11

07 Sep '11

Hi Vicente, Thank you for the reply. When I took a look at codes under "thread', I found there are some places where BOOST_NO_ANSI_APIS is related ( for example in once.hpp ) #ifdef BOOST_NO_ANSI_APIS typedef wchar_t once_char_type #else typedef char once_char_type #endif There is no relation between both librairies that I'm aware of. If you are more explicit with the problem you have, maybe we can help you better. Best, Vicente BTW, don't top post and please send message in text only mode.

1 0

boost::xpressive Error 2668 call to amibous function
by Jens Saathoff 07 Sep '11

07 Sep '11

Hi! I get the error C2668 if i try to compile the following code(xpressive example from docs): #include <string> #include <iostream> #include <boost/xpressive/xpressive.hpp> #include <boost/xpressive/regex_actions.hpp> #include <map> using namespace boost::xpressive; int main() { std::map<std::string, int> result; std::string str("aaa=>1 bbb=>23 ccc=>456"); // Match a word and an integer, separated by =>, // and then stuff the result into a std::map<> sregex pair = ( (s1= +_w) >> "=>" >> (s2= +_d) )[ ref(result)[s1] = as<int>(s2) ]; // Match one or more word/integer pairs, separated // by whitespace. sregex rx = pair >> *(+_s >> pair); if(regex_match(str, rx)) { std::cout << result["aaa"] << '\n'; std::cout << result["bbb"] << '\n'; std::cout << result["ccc"] << '\n'; } return 0; } The complete error: D:\Projekte\xpressive-test\main.cpp:29: Fehler:C2668: 'boost::xpressive::ref' : ambiguous call to overloaded function D:\Frameworks\boost\boost_147\boost/xpressive/regex_actions.hpp(850): could be 'const boost::xpressive::reference<T> boost::xpressive::ref<std::map<_Kty,_Ty>>(T &)' with [ T=std::map<std::string,int>, _Kty=std::string, _Ty=int ] C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\INCLUDE\xrefwrap(439): or 'std::tr1::reference_wrapper<_Ty> std::tr1::ref<std::map<_Kty,int>>(_Ty &)' [found using argument-dependent lookup] with [ _Ty=std::map<std::string,int>, _Kty=std::string ] while trying to match the argument list '(std::map<_Kty,_Ty>)' with [ _Kty=std::string, _Ty=int ] What's the problem here? Thank you very much!

2 2

[boost.thread?][1.46.1] "memory clobbered before allocated block"
by Igor Gorbunov 07 Sep '11

07 Sep '11

Hello, I've ran across a strange bug. GCCs mcheck reports "memory clobbered before allocated block". Reproducible (not every run) with the following test program when executed from gdb: ----- #include <boost/thread.hpp> void proc_func(){ std::vector<int> v1(1024); } int main() { std::vector<int> v2(1024); boost::thread t1(proc_func); t1.join(); } ----- The same test program runs fine (or I'm not been able to trigger this bug) when recompiled with std.thread. I'm in doubt that there is a bug in boost.thread, so maybe build system misconfiguration or gdb bug? stack trace: /home/gie/work/tests/memd1/debug/test [18157] [cores: 0] Thread [2] 18160 [core: 0] (Suspended : Signal : SIGABRT:Aborted) *__GI_raise() at raise.c:64 0x7ffff70d0405 *__GI_abort() at abort.c:92 0x7ffff70d3680 __libc_message() at libc_fatal.c:189 0x7ffff7106dbb *__GI___libc_fatal() at libc_fatal.c:200 0x7ffff7106e9e mabort() at mcheck.c:366 0x7ffff7117aea checkhdr() at mcheck.c:117 0x7ffff71172eb freehook() at mcheck.c:190 0x7ffff71175dc __nptl_deallocate_tsd() at pthread_create.c:155 0x7ffff6e88129 start_thread() at pthread_create.c:311 0x7ffff6e88b4e clone() at clone.S:112 0x7ffff717336d 0x0 Thread [1] 18157 [core: 0] (Suspended : Container) pthread_join() at pthread_join.c:89 0x7ffff6e89e65 boost::thread::join() at thread.cpp:234 0x7ffff7bd2bba main() at main.cpp:12 0x409212 build log: /usr/bin/make all /usr/bin/cmake -H/home/gie/work/tests/memd1/src -B/home/gie/work/tests/memd1/debug --check-build-system CMakeFiles/Makefile.cmake 0 /usr/bin/cmake -E cmake_progress_start /home/gie/work/tests/memd1/debug/CMakeFiles /home/gie/work/tests/memd1/debug/CMakeFiles/progress.marks /usr/bin/make -f CMakeFiles/Makefile2 all make[1]: Entering directory `/home/gie/work/tests/memd1/debug' /usr/bin/make -f CMakeFiles/test.dir/build.make CMakeFiles/test.dir/depend make[2]: Entering directory `/home/gie/work/tests/memd1/debug' cd /home/gie/work/tests/memd1/debug && /usr/bin/cmake -E cmake_depends "Unix Makefiles" /home/gie/work/tests/memd1/src /home/gie/work/tests/memd1/src /home/gie/work/tests/memd1/debug /home/gie/work/tests/memd1/debug /home/gie/work/tests/memd1/debug/CMakeFiles/test.dir/DependInfo.cmake --color= make[2]: Leaving directory `/home/gie/work/tests/memd1/debug' /usr/bin/make -f CMakeFiles/test.dir/build.make CMakeFiles/test.dir/build make[2]: Entering directory `/home/gie/work/tests/memd1/debug' /usr/bin/cmake -E cmake_progress_report /home/gie/work/tests/memd1/debug/CMakeFiles 1 [100%] Building CXX object CMakeFiles/test.dir/main.cpp.o /usr/bin/c++ -g -I/home/gie/work/tests/memd1/debug -std=c++0x -Wall -Wextra -pedantic -o CMakeFiles/test.dir/main.cpp.o -c /home/gie/work/tests/memd1/src/main.cpp Linking CXX executable test /usr/bin/cmake -E cmake_link_script CMakeFiles/test.dir/link.txt --verbose=1 /usr/bin/c++ -g CMakeFiles/test.dir/main.cpp.o -o test -rdynamic -lmcheck -lboost_thread-mt make[2]: Leaving directory `/home/gie/work/tests/memd1/debug' /usr/bin/cmake -E cmake_progress_report /home/gie/work/tests/memd1/debug/CMakeFiles 1 [100%] Built target test make[1]: Leaving directory `/home/gie/work/tests/memd1/debug' /usr/bin/cmake -E cmake_progress_start /home/gie/work/tests/memd1/debug/CMakeFiles 0 -- With best regards, Igor.

1 0

Compiler errors using boost/program_options with Boost v 1.47
by Jakob S. 07 Sep '11

07 Sep '11

Dear all, I use boost/program_options in one of my programs (I compile under Linux with gcc 4.4.3). With Boost 1.46 everything worked fine, but now I installed Boost 1.47 and I get a bunch of error messages: btw, include/Config.hh:28 is simply: Sorry for the plain question, but: Could you help me to fix this? Am I missing something in my installation? Has boost/program_options not be correctly updated to 1.47? Many thanks for your help... -- View this message in context: http://boost.2283326.n4.nabble.com/Compiler-errors-using-boost-program-opti… Sent from the Boost - Users mailing list archive at Nabble.com.

3 2

Example HTTP Server 3, Requests are processed one by one on Win32?
by Sven 07 Sep '11

07 Sep '11

Hi, I'm new to boost and it's mailing list and I really like the library! As my first example project, I want to run the boost HTTP Server 3. Interesting points for me are Socket and Threading stuff. To get into the threading stuff, I did add some output to the std::cout in the request_handler part at the top of the method "handle_request" following by a sleep(5000). After this I compile (without errors/warnings) and run the program providing Ip/Port, docroot and threadpool size 20. When I start a request to it with my browser, as expected I get the output on the console. But when I start some requests concurrent, the requests seems processed one by one ( not concurrent as expected). I don't know, but I expect, that the Requests would be processed concurrent (1 Request = 1 Thread?) I'm using Visual Studio 10 with boost 1.47.0 on windows server 2k8 rc2 and following example code: http://www.boost.org/doc/libs/1_47_0/doc/html/boost_asio/examples.html#boost _asio.examples.http_server_3 Any suggestions? Thanks in advance Sven

3 6

[MultiArrrat] Unbalanced multi_array<>
by Júlio Hoffimann 07 Sep '11

07 Sep '11

Dear all, By reading Boost.MultiArray docs, i haven't figured out any possible way to deal with unbalanced matrices. The following picture explains what i mean by unbalanced: // two dimensional unbalanced matrix: a00 a01 a02 a03 a04 a05 a06 a07 a08 a10 a11 a12 a13 a14 a20 a21 a22 a30 a31 a40 Each row has it's own extent (defined at runtime). Seems multi_array<> classes are not designed to increase it's subcontainers decoupled, and at a given depth, they always share the same extent? Could you confirm or guide me in how to achieve this behavior? I really need to save memory due to large 3D matrices. Regards, Júlio.

2 2

Wave Preprocessor without Using a Lexer
by Alexander Feldman 07 Sep '11

07 Sep '11

Does anybody know how to use the wave preprocessor *without* using the cpp lexer? Best, -- Alex

1 0

boost::lexical_cast: where to declare operator<<
by Nagaev Boris 07 Sep '11

07 Sep '11

Hello! I'm implementing boost::lexical_cast for class A. When operator<< is declared in the same namespace, as class A, it works: * #include <boost/lexical_cast.hpp> * #include <string> * * namespace abc { * * struct A { * int a; * }; * * std::ostream& operator<<(std::ostream& o, const A& a) { * return o << a.a; * } * * } * * int main() { * abc::A a; * std::string a_str = boost::lexical_cast<std::string>(a); * } But if operator<< is declared in root namespace, it will not compile: * #include <boost/lexical_cast.hpp> * #include <string> * * namespace abc { * * struct A { * int a; * }; * * } * * std::ostream& operator<<(std::ostream& o, const abc::A& a) { * return o << a.a; * } * * int main() { * abc::A a; * std::string a_str = boost::lexical_cast<std::string>(a); * } Part of error message: In file included from error.cpp:2:0: /usr/include/boost/lexical_cast.hpp: In member function ‘bool boost::detail::lexical_stream<Target, Source, Traits>::operator<<(const Source&) [with Target = std::basic_string<char>, Source = abc::A, Traits = std::char_traits<char>]’: /usr/include/boost/lexical_cast.hpp:1151:13: instantiated from ‘Target boost::detail::lexical_cast(typename boost::call_traits<Source>::param_type, CharT*, size_t) [with Target = std::basic_string<char>, Source = abc::A, bool Unlimited = true, CharT = char, typename boost::call_traits<Source>::param_type = const abc::A&, size_t = long unsigned int]’ /usr/include/boost/lexical_cast.hpp:1174:77: instantiated from ‘Target boost::lexical_cast(const Source&) [with Target = std::basic_string<char>, Source = abc::A]’ error.cpp:19:59: instantiated from here /usr/include/boost/lexical_cast.hpp:595:48: error: no match for ‘operator<<’ in ‘((boost::detail::lexical_stream<std::basic_string<char>, abc::A, std::char_traits<char> >*)this)->boost::detail::lexical_stream<std::basic_string<char>, abc::A, std::char_traits<char> >::stream << input’ /usr/include/c++/4.5/ostream:108:7: note: candidates are: So, it does not see my declaration. However, <code>std::cout << a << std::endl;</code> works in both cases. What is the reason of this error? Why operator<< can not be declared in root namespace? Sorry for my question. Maybe, it is connected less to boost than to c++. Regards.

2 1

[Interprocess] hang locking p_hdr->m_mutex
by David Byron 06 Sep '11

06 Sep '11

I've got my machine (Win 7) into a state where using a message queue results in a hang. More specifically, calls to: scoped_lock<interprocess_mutex> lock(p_hdr->m_mutex); hang forever. As a bit more background, there's a message queue that holds up to 5 x 1024 byte messages, and I believe currently has 2. I'm having a hard time verifying that because calls to get_num_msg() hang trying on calls like the one above, but that's what I see when I look in c:/ProgramData/boost_interprocess/20110816195406.550541/CliIPC. I have feeling what happened is that some process that was using the message queue got terminated while holding the p_hdr->m_mutex. Does anyone have any suggestions for recovering from this? I'm using version 1.47. Thanks for your help. -DB

2 10

Which encryption algorithm is used in Boost::Asio and SSL?
by Andi Clemens 06 Sep '11

06 Sep '11

Hi, I searched the web for some time now, but I was not able to find out which encryption algorithm is used when using SSL with Boost::Asio. Is there a standard algorithm or do the communicating sockets handle out some method? Andi

1 0

[Spirit] compilation problem
by Igor R 06 Sep '11

06 Sep '11

Hello, I've upgraded to 1.47, and any attempt to include a Spirit header produces the following compiler error (MSVC 10): #include <boost/spirit/include/qi.hpp> int main() { } "../spirit/home/support/detail/endian.hpp(22): fatal error C1083: Cannot open include file: 'boost/integer/endian.hpp': No such file or directory" The error is in the following lines: // If Boost has the endian library, use it, otherwise use an adapted version // included with Spirit #if BOOST_VERSION >= 104600 #include <boost/integer/endian.hpp> #else #include <boost/spirit/home/support/detail/integer/endian.hpp> #endif Actually, there's no boost/integer/endian.hpp file in the zip that I've downloaded. What am I doing wrong? Thanks.

1 1

[serialization] boost::serialization adds huge amounts of exports to resultant Windows PE file
by Matheus Peschke de Azevedo 06 Sep '11

06 Sep '11

Chris, Boost serialization defaults lots of classes/functions to be automatically exported. This is done in \boost\serialization\force_include.hpp: #if defined(BOOST_HAS_DECLSPEC) && !defined(__COMO__) # if defined(__BORLANDC__) # define BOOST_DLLEXPORT __export # else # define BOOST_DLLEXPORT __declspec(dllexport) # endif #elif ! defined(_WIN32) && ! defined(_WIN64) # if defined(__MWERKS__) # define BOOST_DLLEXPORT __declspec(dllexport) # elif defined(__GNUC__) && (__GNUC__ >= 3) # define BOOST_USED __attribute__ ((used)) # elif defined(__IBMCPP__) && (__IBMCPP__ >= 1110) # define BOOST_USED __attribute__ ((used)) # elif defined(__INTEL_COMPILER) && (BOOST_INTEL_CXX_VERSION >= 800) # define BOOST_USED __attribute__ ((used)) # endif #endif The easiest workaround for this is: 1. Place your serialization #include lines in a precompiled header. 2. Right after all your boost serialization #includes, write this: #ifdef BOOST_DLLEXPORT #undef BOOST_DLLEXPORT // it was '__declspec(dllexport)' #define BOOST_DLLEXPORT // now it's '' #endif Just rebuild your project and you'll see all exports gone. No need to recompile boost serialization lib as functions affected are templates. Regards, Matheus

1 0

boost bind() error for creating thread
by Jack Bryan 05 Sep '11

05 Sep '11

Hi, I using boost::bind() to create thread. But, I got errors at: threadGroup.create_thread(boost::bind(&lab1::Server::Run, server)); Any help is really appreciated. Code is as follows: --------------------------------------------- class Server {public: // The constructor takes a port number and prepares to receive HTTP // requests from clients on that port. explicit Server(int port); // Closes the connection. ~Server(); // void Run(); //Server(Server&);private: // 'listening' socket used to establish HTTP connections int listen_fd_; // Non-copyable, non-assignable Server(Server&); Server& operator=(Server&);}; int main(int argc, char *argv[]) { if (argc != 2) { std::cout << "Usage: lab1 <port>" << std::endl; return 1; } // Convert the port from a string to an integer. int port_number; std::istringstream port_stream(argv[1]); // argv[1] is port number, port_stream >> port_number; // Convert the thread number from a string to an integer. int thread_number; std::istringstream thread_stream(argv[2]); // argv[1] is port number, thread_stream >> thread_number; lab1::Server server(port_number); boost::thread_group threadGroup; for(int i=0;i<thread_number;i++) { threadGroup.create_thread(boost::bind(&lab1::Server::Run, server)); }threadGroup.join_all(); return 0;} error: no matching function for call to âboost::_bi::bind_t<void, boost::_mfi::mf0<void, lab1::Server>, boost::_bi::list1<boost::_bi::value<lab1::Server> > >::bind_t(boost::_bi::bind_t<void, boost::_mfi::mf0<void, lab1::Server>, boost::_bi::list1<boost::_bi::value<lab1::Server> > >)â /bind.hpp:865: note: candidates are: boost::_bi::bind_t<void, boost::_mfi::mf0<void, lab1::Server>, boost::_bi::list1<boost::_bi::value<lab1::Server> > >::bind_t(boost::_bi::bind_t<void, boost::_mfi::mf0<void, lab1::Server>, boost::_bi::list1<boost::_bi::value<lab1::Server> > >&) lab2.cpp:241: error: initializing argument 1 of âboost::thread* boost::thread_group::create_thread(F) [with F = boost::_bi::bind_t<void, boost::_mfi::mf0<void, lab1::Server>, boost::_bi::list1<boost::_bi::value<lab1::Server> > >]â bind_mf_cc.hpp: In function âboost::_bi::bind_t<R, boost::_mfi::mf0<R, T>, typename boost::_bi::list_av_1<A1>::type> boost::bind(R (T::*)(), A1) [with R = void, T = lab1::Server, A1 = lab1::Server]â error: initializing argument 1 of âboost::thread* boost::thread_group::create_thread(F) [with F = boost::_bi::bind_t<void, boost::_mfi::mf0<void, lab1::Server>, boost::_bi::list1<boost::_bi::value<lab1::Server> > >]â instantiated from herebind_mf_cc.hpp:24: error: no matching function for call to âboost::_bi::list1<boost::_bi::value<lab1::Server> >::list1(boost::_bi::list1<boost::_bi::value<lab1::Server> >)â

2 3

Re: [Boost-users] [boost] [Review] Boost.Endian by BEman Dawes starts today
by Hartmut Kaiser 05 Sep '11

05 Sep '11

> According to the schedule, the review of the Boost.Endian library by Beman > Dawes starts today. > > =========== > What is it? > =========== > > Boost.Endian provides facilities to manipulate the byte ordering of > integers. > > * The primary use case is binary I/O of integers for portable exchange > with other systems, via either file or network transmission. > > * A secondary use case is to minimizing storage size via integers of sizes > and/or alignments not supported by the built-in types. Integers 1, 2, 3, > 4, 5, 6, 7, and 8 bytes in length are supported. > > * Two distinct approaches to byte ordering are provided. Each approach has > a long history of successful use, and each approach has use cases where it > is superior to the other approach. > > * The explicit approach provides explicit functions to reorder bytes. > All four combinations of non-modifying or modifying, and unconditional or > conditional, functions are provided. > > * The implicit approach provides integer classes that mimic the built-in > integers, implicitly handling all byte reordering. Even if this is not a full review, I would like to vote YES to include this library into Boost. Boost.Spirit is using (and shipping) with an older version of this library for several years now and we never had any problems with its usage in Spirit. It is used as the underlying framework for the binary parsers and generators and it is functioning as advertised. As a quick test I replaced the internal (older) version of Boost.Endian in Spirit with the reviewed version. All of Spirits regression tests still pass. Regards Hartmut --------------- http://boost-spirit.com > > =================== > Getting the Library > =================== > > Docs are available at http://boost.cowic.de/rc/endian/doc/index.html > A zip file is available at http://boost.cowic.de/rc/endian/endian-rc1.zip > INSTALL instructions at http://boost.cowic.de/rc/endian/INSTALL > > Alternately, the whole library can be checked out of the sandbox: > > svn co http://svn.boost.org/svn/boost/sandbox/endian endian > > ================ > Writing a Review > ================ > > The reviews and all comments should be submitted to the developers list, > and the email should have "[Endian] Review" at the beginning of the > subject line to make sure it's not missed. > > Please explicitly state in your review whether the library should be > accepted. > > The general review checklist: > > - What is your evaluation of the design? > - What is your evaluation of the implementation? > - What is your evaluation of the documentation? > - What is your evaluation of the potential usefulness of the > library? > - Did you try to use the library? With what compiler? Did you > have any problems? > - How much effort did you put into your evaluation? A glance? A > quick reading? In-depth study? > - Are you knowledgeable about the problem domain? > > And finally, every review should answer this question: > > - Do you think the library should be accepted as a Boost library? > > Be sure to say this explicitly so that your other comments don't obscure > your overall opinion. > > > > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost

1 0

Metaprogramming + Multiple Inheritance?
by Hossein Haeri 05 Sep '11

05 Sep '11

Dear all, I am looking for problems a reasonable design for solving which requires mixing (template/preprocessor) metaprogramming and multiple inheritance, say for a single class. In particular, has any part of the Boost library been designed with this mixture? TIA,--Hossein

3 6

[meta-state-machine] Flag_AND doesn't work
by Péter Szabados 05 Sep '11

05 Sep '11

Hi, I am using Boost 1.47.0, and wrote a state machine in MSM with 2 parallel regions. In each region, one state has a flag defined. According to the documentation, when I ask the flag the following way: sm.is_flag_active<FlagStarted, StateMachine::Flag_AND>() then it returns true if both regions are in a state with the flag. However, it doesn't work for me. I have attached an example of this problem. It has the states Stopped1, Started1 and Stopped2, Started2 for the two regions respectively. The states Started1 and Started2 has the flag FlagStarted attached. The flag is checked after each call of process_event. The output of the program is the following: Entering Stopped1 Entering Stopped2 (sm.is_flag_active<FlagStarted, StateMachine::Flag_OR>()): no (sm.is_flag_active<FlagStarted, StateMachine::Flag_AND>()): no Leaving Stopped1 Entering Started1 (sm.is_flag_active<FlagStarted, StateMachine::Flag_OR>()): yes (sm.is_flag_active<FlagStarted, StateMachine::Flag_AND>()): no Leaving Stopped2 Entering Started2 (sm.is_flag_active<FlagStarted, StateMachine::Flag_OR>()): yes (sm.is_flag_active<FlagStarted, StateMachine::Flag_AND>()): no After the second transition, we are in state (Started1, Started2). The flag should be active here, but it isn't. Is there a problem with MSM, or am I doing something wrong? -- Péter

2 1

zip_iterator documentation: probably malformed example
by Krzysztof Żelechowski 05 Sep '11

05 Sep '11

At [http://www.boost.org/doc/libs/1_47_0/libs/iterator/doc/zip_iterator.html Zip Iterator]: is:: {{{zip_it->get<0>() = 42.0;}}} (syntax error) works:: {{{zip_it -> template get <0> () = 42.0;}}}

3 3

exceptions from boost::filesystem not catchable on os/x 10.6.8 boost-1.47.0
by david x callaway 05 Sep '11

05 Sep '11

os/x 10.6.8 uname -a Darwin apple1 10.8.0 Darwin Kernel Version 10.8.0: Tue Jun 7 16:33:36 PDT 2011; root:xnu-1504.15.3~1/RELEASE_I386 i386 boost 1.47.0 ./bootstrap.sh --prefix=$HOME/boost ./b2 link=static --disable-filesystem2 install # I've tried without disabling filesystem2, same result gcc -v Using built-in specs. Target: i686-apple-darwin10 Configured with: /var/tmp/gcc/gcc-5666.3~6/src/configure --disable-checking --enable-werror --prefix=/usr --mandir=/share/man --enable-languages=c,objc,c++,obj-c++ --program-transform-name=/^[cg][^.-]*$/s/$/-4.2/ --with-slibdir=/usr/lib --build=i686-apple-darwin10 --program-prefix=i686-apple-darwin10- --host=x86_64-apple-darwin10 --target=i686-apple-darwin10 --with-gxx-include-dir=/include/c++/4.2.1 Thread model: posix gcc version 4.2.1 (Apple Inc. build 5666) (dot 3) test app compiled: g++ -Wall -I $HOME/boost/include fs.cpp -L$HOME/boost/lib -lboost_filesystem -lboost_system otool -L a.out a.out: /usr/lib/libstdc++.6.dylib (compatibility version 7.0.0, current version 7.9.0) /usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 125.2.11) source below. when I run it with a non-existent filename I expect to catch an exception, but instead nothing happens, i.e. I just return to the shell prompt. I tried defining a struct locally and throwing it and the catch works fine. any ideas? thx dxc ------------------------------------------------------------ #include <iostream> #include <stdlib.h> #include "boost/filesystem.hpp" int main(int argc, const char** argv) { if(argc != 2) { std::cout << "usage: a.out filename\n"; exit(1); } const char* a_path = argv[1]; try { boost::filesystem::exists(a_path); } catch(const boost::filesystem::filesystem_error& e) { std::cout << "caught filesystem_error\n"; std::cout << e.what() << "\n"; exit(1); } catch(const std::exception& e) { std::cout << "caught some other error\n"; std::cout << e.what() << "\n"; exit(1); } catch(...) { std::cout << "caught unknown exception\n"; exit(1); } return 0; }

3 3

Using boost function input iterator with class member functions
by Michael King 05 Sep '11

05 Sep '11

Hello, I am trying to use a class member function in conjunction with boost's function input iterator, and am having trouble coming up with a solution which can in any way be considered elegant... My initial thought process was to do something like : std::copy( // does not work because the functor (1st arg to make_function_input iterator ) cannot be temporary... or something like that boost::make_function_input_iterator(boost::bind(&My_Class::my_function, 0)), boost::make_function_input_iterator(boost::bind(&My_Class::my_function, 10)), std::ostream_iterator<result_type>(std::cout, " ") ); However, this fails as noted above. Thus, i had to look at some compiler error messages in order to figure out the return type of boost::bind and create some boost::bind object producing the working code below, however, this looks pretty terrible. Can anyone suggest a more convenient solution to the problem I am trying to solve? Thanks, Michael King #include<iostream> #include<iterator> #include<boost/bind.hpp> #include<boost/iterator/function_input_iterator.hpp> class foo { public: typedef double result_type; result_type return_random() const { return drand48(); } }; int main() { foo bar; // found type from compiler error message... boost::_bi::bind_t< double, boost::_mfi::cmf0< double, foo>, boost::_bi::list1< boost::_bi::value<foo> > > f = boost::bind(&foo::return_random, bar); std::copy( boost::make_function_input_iterator(f, 1), boost::make_function_input_iterator(f, 10), std::ostream_iterator<double>(std::cout, "\n") ); return 0; }

2 1

linking with libboost_graph not enough, but libboost_regex required?
by Oliver Kullmann 04 Sep '11

04 Sep '11

Hello, we have some legacy code, which after a change of system no longer runs: The new system is Boost 1.44.0 under Linux (Suse 11.4 for the record), but compiling with gcc version 4.1.2. > uname -a Linux csnereid 2.6.37.1-1.2-desktop #1 SMP PREEMPT 2011-02-21 10:34:10 +0100 i686 i686 i386 GNU/Linux We have a simple application which reads a graph-file and performs a simple computation. It links to libboost_graph. Apparently that draws in the libboost_regex, but that used to work: On the older installation (Suse 10.0 for the record) we had for the application > ldd Application libboost_graph.so.1.44.0 => /home/csoliver/SAT-Algorithmen/OKplatform/ExternalSources/Installations/Boost/4.1.2/1_44_0/lib/libboost_graph.so.1.44.0 (0x00002aaaaabc2000) libboost_regex.so.1.44.0 => /home/csoliver/SAT-Algorithmen/OKplatform/ExternalSources/Installations/Boost/4.1.2/1_44_0/lib/libboost_regex.so.1.44.0 (0x00002aaaab6f5000) and we see that at that time, also with Boost 1.44.0, linking was established to the local Boost installation, the same for libboost_graph and libboost_regex. However, now this implicit addition of the regex-link-library (which is managed by the Graph-library itself, not visible to the user --- I can't find the boost-regex-library anywhere mentioned in the Boost-Graph-documentation) does not work anymore --- if there is a system-wide Boost installation, it uses that, and otherwise it breaks: libboost_graph.so.1.44.0 => /home/csoliver/OKplatform/ExternalSources/Installations/Boost/4.1.2/1_44_0/lib/libboost_graph.so.1.44.0 (0x00007f8170fbe000) libboost_regex.so.1.44.0 => /usr/lib64/libboost_regex.so.1.44.0 (0x00007f81701c1000) libboost_graph.so.1.44.0 => /compsci/saturn/staff/csoliver/OKplatform/ExternalSources/Installations/Boost/4.1.2/1_44_0/lib/libboost_graph.so.1.44.0 (0xb7774000) libboost_regex.so.1.44.0 => not found I guess linking explicitly to libboost_regex would solve the problem, but that's under the circumstances not so easy to do, and furthermore something seems wrong here, and I would like to know what (it shouldn't be needed to link to libboost_regex, or, if so, then it should be documented). Thanks for your consideration! Oliver

2 2

boost::zip_iterator does not work with std::istreambuf_iterator
by Krzysztof Żelechowski 04 Sep '11

04 Sep '11

1. boost::zip_iterator requires a readable iterator. 2. std::istreambuf_iterator is a readable iterator. 3. boost::zip_iterator cannot dereference std::istream_iterator because std::istreambuf_iterator returns by value while boost::zip_iterator returns by reference; the exact error message is invalid initialization of non-const reference of type ‘char&’ from an rvalue of type ‘std::istreambuf_iterator<char, std::char_traits<char> >::char_type’ Contradiction? Am I missing anything? Chris

2 2

boost serialization help
by ohad barta 04 Sep '11

04 Sep '11

Hi My name is Ohad, and I work for the Technion institution, Israel. We are currently working on a research that involves programming in C++, and for that project we are using the serialization module of Boost. I'm not sure if this is the place to ask for help with boost. If not, Could you please direct me to the right address? my problems: 1) does the following supposed to work? : I have a : class saving helper{ boost::archive::binary_archive* ar; } and: class Y { X* first vector <Y*> second } and I try to save Y with the saving helper: for each level of Y object I initialize a saving helper, directly call a function that does *ar & * first (the function name isnt serialize\save) for each Y* on the next level I create a new saving helper object with a new pointer, initiallized the same: saving_helper::saving_helper(saving_helper* to_copy){ this->ar = to_copy->ar;} and continue saving the very same object (another level) with the new saving helper (the load is standard - via a regualr load function) I know that this is not the standard way to use boost, but I dont have much choice. 2) When trying to use the above method with text archive, I always get a streaming error, but If I use a binary archive than the streaming error vanished and instead I start to read the file from its middle (i.e. read the forth number instead of the first, reading the fifth bumber instead the second,etc). increasing the file length by adding to it 3 redundent numbers solved those two problems, and yet Im looking for a more stable solution, so help will be apprecialted. 3) boost tracking: where should I put the BOOST_CLASS_TRACKING macro? I currently use: boost 1.47.0 visual studio 2010 OS windows 7 Thanks in advance Ohad

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Subclassing "position_iterator"
by Alexander Feldman 04 Sep '11

04 Sep '11

Hi, I have the following question. I want to subclass/implement a new position_iterator that recognizes lines such as: #line 11 "electrical.lcl" and updates accordingly its location. My question is how to do that in the most elegant manner. Shall I copy/paste "position_iterator.hpp" and hack the increment() method? Would you, guys, use a Qi parser to recognize these lines? Maybe there is a better way... Thanks, -- Alex

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Asio example 5 sagmentation fault
by Alessandro Candini 04 Sep '11

04 Sep '11

I'm really interested in exemple 5 of boost asio: http://www.boost.org/doc/libs/1_47_0/doc/html/boost_asio/tutorial/tuttimer5… I've tried it with boost-1.47.0. I can compile without warnings using: g++ -Wall -pedantic -lboost_thread -lboost_system -o timer5 timer5.cpp but when I launch the executable it gives me a Segmentation fault. Commenting the code I found that the segmentation fault raise at the 3rd line of main: boost::thread t(boost::bind(&boost::asio::io_service::run, &io)); I'm trying on the following machine: Linux office-007 2.6.38-11-generic #48-Ubuntu SMP Fri Jul 29 19:02:55 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux Can anyone help me? -- Alessandro Candini MEEO S.r.l. Via Saragat 9 I-44122 Ferrara, Italy Tel: +39 0532 1861501 Fax: +39 0532 1861637 http://www.meeo.it ======================================== "ATTENZIONE:le informazioni contenute in questo messaggio sono da considerarsi confidenziali ed il loro utilizzo è riservato unicamente al destinatario sopra indicato. Chi dovesse ricevere questo messaggio per errore è tenuto ad informare il mittente ed a rimuoverlo definitivamente da ogni supporto elettronico o cartaceo." "WARNING:This message contains confidential and/or proprietary information which may be subject to privilege or immunity and which is intended for use of its addressee only. Should you receive this message in error, you are kindly requested to inform the sender and to definitively remove it from any paper or electronic format."

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