October 2014 - Boost-users - lists.boost.org

[interprocess] Determine size of managed_shared_memory
by Kai Benndorf 12 Oct '19

12 Oct '19

Hi all, I want to create a managed_shared_memory in exactly the size I needed. Therefore I do something like this: size = sizeof( common_managed_shared_memory ); size += sizeof( MyClassInSharedMem ); managed_shared_memory segment(create_only, "name", size ); MyClassInSharedMem allocates itself some memory by segment->allocate(). I added this also to the size, but get a boost::interprocess::bad_alloc exception on allocating this additional memory. Are there some magic bytes I forgot to add? Many thanks in advance Kai

3 2

[Range, Phoenix] What am I missing...
by Robert Jones 25 Apr '17

25 Apr '17

Hi Folks Can anyone explain the output of this program... #include <iostream> #include <boost/range/algorithm/copy.hpp> #include <boost/range/counting_range.hpp> #include <boost/range/adaptor/reversed.hpp> #include <boost/range/adaptor/transformed.hpp> #include <boost/phoenix/bind/bind_function.hpp> #include <boost/phoenix/core/argument.hpp> int f( int i ) { return i * 2; } int main( ) { using boost::adaptors::reversed; using boost::adaptors::transformed; using boost::counting_range; using boost::copy; using boost::phoenix::arg_names::_1; copy( counting_range( 1, 5 ) | reversed | transformed( f ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; copy( counting_range( 1, 5 ) | reversed | transformed( bind( f, _1 ) ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; } Which is... 8 6 4 2 1768406272 1768406272 1768406272 1768406272 I'm using Gcc 4.6.2 & Boost 1.53 Thx All.

3 4

[statechart] Passing parameters from event to State Local Storage
by Christophe Bourez 16 Nov '16

16 Nov '16

I need to maintain a parameter into the state local storage. This parameter is initially contained in the event that causes the transition to the target state. I give hereafter a small illustrative example. typename sc = boost::statechart; class EvTest : public sc::event<EvTest> { public: EvTest(std::size_t val) : value(val) {} std::size_t getValue() const { return this->value; } private: std::size_t value; }; class MyStateMachine; class StSource; class StTarget; class StSource : public sc::simple_state<StSource, MyStateMachine> { public: typedef sc::custom_reaction<EvTest> reactions; sc::result react(const EvTest &event) { // How to pass event.getValue() to the target state ? transit<StTarget>(); } }; class StTarget : public sc::simple_state<StTarget, MyStateMachine> { public: StTarget(std::size_t val) : val(value) {} private: std::size_t value; }; Thanks, Christophe

5 6

Re: [Boost-users] lexical_cast between double and string slow in Visual Studio 2013
by David Roberts 07 May '15

07 May '15

> That issue is unknown. I'd really appreciate the investigation. I have done some more investigation, and there are two factors that only cause the slowness when they both occur together. > Try excluding the lexical_cast from test, I have a feeling that this is only MSVC related issue: > > #include <sstream> > #include <string> > > int main (int, char **) > { > for (double count = 0.0; count < 1000000.0; count += 1.41) > { > std::stringstream ss; > ss << count; > std::string result = std::move(ss.str()); > ss.str(std::string()); > > ss << result; > ss >> count; > } > > return 0; > } > Running your test program does not exhibit the problem. It runs in around 3 seconds on my machine when built with either Visual Studio 2010 or Visual Studio 2013. However, changing it very slightly to match more closely what lexical_cast does internally does recreate the problem: #include <sstream> #include <string> int main (int, char **) { for (double count = 0.0; count < 1000000.0; count += 1.41) { std::stringstream ss; ss.unsetf(std::ios::skipws); ss.precision(17); ss << count; std::string result = std::move(ss.str()); ss.str(std::string()); ss << result; ss >> count; } return 0; } The effect of setting the precision to 17 is that lots of 9s appear in the string representations. (The number 17 is what boost::detail::lcast_get_precision(double*) chooses.) Without the precision call the contents of the string called result start off like this: 0 1.41 2.82 4.23 5.64 7.05 8.46 9.87 11.28 12.69 With precision set to 17 they start off like this: 0 1.4099999999999999 2.8199999999999998 4.2299999999999995 5.6399999999999997 7.0499999999999998 8.4599999999999991 9.8699999999999992 11.279999999999999 12.69 This happens for both Visual Studio 2010 and Visual Studio 2013. Then the next difference is that Visual Studio 2013 spends a lot longer handling all the extra 9s. Changing the program so that the double is converted to a string using std::stringstream without a precision call and then back to double using lexical_cast takes about 3 seconds for both Visual Studio 2010 and Visual Studio 2013. It is the combination of having all the extra 9s to parse and using Visual Studio 2013 that makes the test using lexical_cast to go both ways slow. Both Visual Studio 2010 and Visual Studio 2013 do the conversion by calling std::num_get<char,std::istreambuf_iterator<char,std::char_traits<char> > >::do_get() which then calls a function called _Stodx() which is implemented in xstod.c. This function is very different for the two versions. In Visual Studio 2010 it's a relatively thin wrapper around the C function strtod(). In Visual Studio 2013 _Stodx() has got a completely new implementation that's generated by #including xxstod.h with some macros defined. The original C function strtod() is much faster than the new _Stodx() when there are lots of 9s at the end of the strings being parsed. This modification to the program: #include <sstream> #include <string> #include <stdlib.h> int main (int, char **) { for (double count = 0.0; count < 1000000.0; count += 1.41) { std::stringstream ss; ss.unsetf(std::ios::skipws); ss.precision(17); ss << count; std::string result = std::move(ss.str()); ss.str(std::string()); ss << result; char *endptr; count = strtod(ss.str().c_str(), &endptr); } return 0; } has a runtime of about 3 seconds even though it's got to cope with all the 9s. I guess only someone from Microsoft or Dinkumware could comment on why _Stodx() was reimplemented. But the other thing is that by setting precision to 17 lexical_cast is bloating the string representations of the doubles with lots of 9s in both Visual Studio 2010 and Visual Studio 2013. Setting precision to 15 instead prevents this, and makes the original test run faster even with Visual Studio 2013 (about 4 seconds rather than 10). Regards, David

5 4

[boost.geometry] buffer distance strategies
by gchlebus 09 Mar '15

09 Mar '15

Hi, I am wondering whether it would be possible to achieve anisotropic buffering (distances in neg x, pos x, neg y, pos y can have different values) of a polygon using the buffer function with custom-implemented distance strategy. What I want to achieve is presented on the figure 2-b in the following paper: http://itcnt05.itc.nl/agile_old/Conference/mallorca2002/proceedings/posters… I would be grateful to hear from you whether it is doable, and if positive, how one could implement such a custom distance strategy. Best, -- View this message in context: http://boost.2283326.n4.nabble.com/boost-geometry-buffer-distance-strategie… Sent from the Boost - Users mailing list archive at Nabble.com.

3 24

Statechart serialization
by mbrodeur65 04 Mar '15

04 Mar '15

Hi, I'm looking for a solution to serialize boost::statechart objects. I'm aware that this feature is on the statechart library todo list but was wondering if there are any workaround to achieve this with the latest boost release (1.34) ? thanks for your help ! mbrodeur65 -- View this message in context: http://www.nabble.com/Statechart-serialization-tf4131326.html#a11749139 Sent from the Boost - Users mailing list archive at Nabble.com.

4 4

[multi state machine/ MSM] execute_queued_events
by Steve Hickman 26 Jan '15

26 Jan '15

In the MSM doc section "Enqueueing events for later processing", you state that "Calling execute_queued_events() will then process all enqueued events (in FIFO order)." You also said in a previous post that MSM is not thread safe, thus requiring an external mechanism to insure thread safety. I don't see a mechanism to execute a single event at a time, which would be preferable if I have to lock the queue while processing events. Having said that, a cursory examination of the "execute_queued_events" code makes me think it only processes one event per call. Which is correct? Is the documentation correct that it actually processes all queued events? If not, can the documentation be corrected? If so, is there a publicly usable call to process a single queued event? If there is no publicly available call for processing a single queued event, how do you recommend processing queued events in a thread safe manner that won't lock the queue for extended periods of time?

4 7

[endian] Boost.Endian library added for 1.57.0
by Beman Dawes 14 Dec '14

14 Dec '14

The library provides integer and floating point types and conversion functions for portable byte ordering regardless of processor endianness. Although the primary uses are for file or network I/O, it is also useful for unaligned integers or floats, or for 3, 5, 6, and 7 byte integers. The library's predecessors have been in use for thirty years and developed independently multiple times. The repository is https://github.com/boostorg/endian The documentation is online at https://boostorg.github.io/endian/ See https://boostorg.github.io/endian/index.html#Release-history for changes since the Formal Review. No need to report "Inspection Report" problems; those will be cleaned up before 1.57.0 ships. Please do report any other problems or concerns, since the time between now and when the 1.57.0 beta ships in effect acts a mini-review period. If anyone has access to a big-endian platform with a modern C++ compiler, please, please run the endian test suite and report the results. All testing and use in recent years has been on little-endian platforms, so big-endian platform testing is a worry. Thanks for you patience, --Beman

3 2

Fusion Move Semantics
by Ovanes Markarian 04 Dec '14

04 Dec '14

Hi! I would like to ask does fusion supports move semantics, or are all the values going to get copied. I use C++11 (clang with libstdcxx) and boost 1.54 (but can upgrade). In my use case I have boost::fusion::map and was wondering, that in case of moving of that map, is it going to forward the move call to contained values or not. Many thanks for help, Ovanes

3 2

NT² 3.0 and Boost.SIMD - Stable release
by Joel Falcou 21 Nov '14

21 Nov '14

The first stable release of the 3.x series of MetaScale’s open-source software is available: NT² 3.0. It also includes its spin-off project, Boost.SIMD (not yet a Boost library). Many Issues have been closed since last beta. The main focus of this release cycle was to fix performances issues and to stabilize some parts of the API. Next step will be to separate NT2 and Boost.SIMD into separate repositories, thus making one more step toward Boost.SIMD submission into review. [ http://www.metascale.org/nt%C2%B2-3-0-and-boost-simd ] *Changes & Bug Fixes:* - Major performance improvements in both libraries - Added experimental support for the HPX runtime for parallelization on shared memory systems - Optimizations of many elemental functions, in particuler log/ex, frexp/ldexp and cbrt - More advanced shuffle pattern recognition for SIMD - Fixed issues with Visual Studio 2013 - More functions are force-inlined to ensure good performance - New functions for conversion between types and mixing of vectors of different sizes - Demo applications usable as benchmarks - Better handling of errors when an unsupported function is called - New API for custom memory allocators Full changelog is available at https://github.com/MetaScale/nt2/releases/tag/3.0.0. *How to get it ?* - Source and binary packages can be downloaded here: http://nt2.metascale.org/downloads - The release is also available on Github : https://github.com/MetaScale/nt2/releases - The main master branch is still under development : https://github.com/MetaScale/nt2

4 4

[Test] How to log output to both stdout in HRF and to a file in XML?
by Martin Ba 03 Nov '14

03 Nov '14

As asked on SO: http://stackoverflow.com/questions/26505229/how-to-log-boost-test-output-to… I would like to enable logging of Boost.Test output to *both* the stdout/sterr and to a logfile. However, I would also like to have the stdout logging be in HumanReadableFormat and only the file output be in XML format. Generating a report file seems to be addressed [here][1]. ([official docs][2]) Choosing the format can be done in [various ways][3], but it seems one is stuck with either HRF or XML? ----------- Rationale: When running tests on or [Jenkins][4] server, the [xUnit plugin][5] [requires][6] the **log** XML output (as opposed to the *report* XML output -- `log_level` vs. `report_level`). However, the in-progress log output (in HRF) is highly valuable *while* the tests are running on the server, to detect hanging tests or to a quick manual check of where the tests currently are. So I want an in-progress HRF log for the tests and at the end I need an XML file containing the `<TestLog>...</TestLog>` output of Boost.Test (not the `<TestResult>` output). Do note that we run both unit as well as integration tests via Boost.Test, so some of them are quite long-running. [1]: http://stackoverflow.com/questions/3786639/what-is-the-better-way-to-genera… [2]: http://www.boost.org/doc/libs/1_44_0/libs/test/doc/html/utf/user-guide/test… [3]: http://www.boost.org/doc/libs/1_44_0/libs/test/doc/html/utf/user-guide/runt… [4]: http://jenkins-ci.org/ [5]: https://wiki.jenkins-ci.org/display/JENKINS/xUnit+Plugin [6]: https://issues.jenkins-ci.org/browse/JENKINS-13686

2 1

[1.57.0] Release candidates available
by Marshall Clow 03 Nov '14

03 Nov '14

[ Please disregard previous message; apparently I am brain-dead this morning. The uploaded files are correct, though. ] Release candidate files for 1.57.0 are available at http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. The files (and associated md5s) are: MD5 (./boost_1_57_0_rc1.7z) = 17c98dd78d6180f553fbefe5a0f57d12 MD5 (./boost_1_57_0_rc1.tar.bz2) = 1be49befbdd9a5ce9def2983ba3e7b76 MD5 (./boost_1_57_0_rc1.tar.gz) = 25f9a8ac28beeb5ab84aa98510305299 MD5 (./boost_1_57_0_rc1.zip) = 5e040e578e3f0ba879da04a1e0cd55ff Thanks! -- The release managers P.S. Release notes are here: http://www.boost.org/users/history/version_1_57_0.html

3 3

(no subject)
by Johnny McCullough 01 Nov '14

01 Nov '14

I'm new to boost, and I'm wondering about the best / most efficient way to transfer a large dataset via boost::asio. I've retrieved a datasetfrom a database (Cassandra) and I'm using boost asio to provide a network service that responds to queries. So I have a client socket and a dataset. I have to iterate the dataset, perform some simple formatting (e.g. csv, json, xml), then write it out to the client socket. But there's a lot of data. Perhaps gigabytes. So my initial thoughts were the producer / consumer pattern - the producer writing to a streambuf and the consumer async_write-ing it out to the client's socket. But I'm not sure this is a good approach - I know that streambuf isn't threadsafe and so managing the streambuf with locks may well become a performance bottleneck. Obviously, I don't want to replicate what may be gigabyte(s) of data from a resultset into a buffer just so it can be written out to a socket, So should I write this data synchronously straight to the socket instead? What's the best approach to solving this kind of problem? thanks for your consideration

2 1

From: giridhar
by giridhar 31 Oct '14

31 Oct '14

Hi boost http://mountpleasanthomebuilder.com/brother.php?produce=z3ueg5w3x3gg giridhar Sent from my iPhone

1 0

[1.56.0] Release candidates available
by Marshall Clow 31 Oct '14

31 Oct '14

Release candidate files for 1.65.0 are available at http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. The files (and associated md5s) are: MD5 (./boost_1_57_0_rc1.7z) = 17c98dd78d6180f553fbefe5a0f57d12 MD5 (./boost_1_57_0_rc1.tar.bz2) = 1be49befbdd9a5ce9def2983ba3e7b76 MD5 (./boost_1_57_0_rc1.tar.gz) = 25f9a8ac28beeb5ab84aa98510305299 MD5 (./boost_1_57_0_rc1.zip) = 5e040e578e3f0ba879da04a1e0cd55ff Thanks! -- The release managers P.S. Release notes are here: http://www.boost.org/users/history/version_1_57_0.html

1 0

[PropertyTree][variant] Reading JSON into a recursive variant.
by Arindam Mukherjee 31 Oct '14

31 Oct '14

I have a recursive variant definition that can handle JSON data. Is there a way to read JSON data using PropertyTree into a recursive JSON? Here is the variant defn. #define BOOST_VARIANT_NO_FULL_RECURSIVE_VARIANT_SUPPORT #include <boost/variant.hpp> JSONNullType {}; boost::variant<std::string, double, bool, JSONNullType> jsonToken; typedef boost::make_recursive_variant< std::string, double, JSONNullType, std::map<std::string, boost::recursive_variant_>, std::vector<boost::recursive_variant_> >::type JSONValue; Regards, Arindam

1 0

[Boost.Test]: How I can write custom external main ?
by NtVisigoth 29 Oct '14

29 Oct '14

Hi, Everybody! I've 2 questions about Boost.Test usage. My general cpp-source file appmain.cpp: // more lines with "#include"-constructions #define BOOST_TEST_MODULE TestMain #include <boost/test/unit_test.hpp> My suite-source file suite1.cpp: #include <boost/test/unit_test.hpp> BOOST_AUTO_TEST_SUITE(FooFooSuite) BOOST_AUTO_TEST_CASE(testBarBarBar) { // more lines } BOOST_AUTO_TEST_SUITE_END() Questions #1: How can write external main in my general cpp-file appmain.cpp? I want usage exe-file like : test.exe d:\test-files\ Questions #2: I see these lines in the boost.test documentation: boost::unit_test::framework::master_test_suite().argc boost::unit_test::framework::master_test_suite().argv This args and argv global, are these ? Can I use this in different suites without save to global variable ? P.S.: I sorry for my English.

1 0

[type_traits] Check if implicit conversion from one type to another is possible
by Aaron Levy 29 Oct '14

29 Oct '14

Which is the correct type trait to use to check if an element of type T can be assigned to an element of type U. Is it any of the following: boost::is_convertible<T, U> std::is_assignable<U, T> Now boost::is_convertible<double, int>::value is true while std::is_assignable<int, double>::value is false. What does this signify? -- Aaron Levy aaron.levy(a)yandex.com

1 0

bjam hangs on select (in develop branch)
by Alain Miniussi 28 Oct '14

28 Oct '14

Hi, I am trying to test Boost.MPI with Intel's implementation and I am stuck while trying to run simple tests through bjam. Bjam is hangs on the select (not pselect ?) instruction of the unix exec_wait. As far as processes are concerned: PID USER PR NI S %CPU TIME+ PPID COMMAND ....................... 16882 alainm 20 0 S 0.0 0:01.61 6507 bjam 16899 alainm 20 0 T 0.0 0:00.00 16882 sh 16900 alainm 20 0 Z 0.0 0:00.00 16899 mpiexec.hydra <defunct> ....... bjam calls a generated shell (below) which calls a mpiexe.hydra which work perfectly fine outside bjam. The mpiexec.hydra dies the the shell refuses to let it go. the shell script, generated by bjam, is: =============================================== [alainm@gurney engine]$ more /proc/16899/cmdline /bin/sh LD_LIBRARY_PATH="/gpfs/scratch/alainm/view/boost/bin.v2/libs/mpi/build/intel-linux/debug:/gpfs/scratch/alainm/view/boost/bin.v2/libs/serialization/build/intel-linux/debug:/softs/ intel/composer_xe_2015.0.090/bin/lib:/softs/intel/composer_xe_2015.0.090/lib/intel64:$LD_LIBRARY_PATH" export LD_LIBRARY_PATH status=0 if test $status -ne 0 ; then echo Skipping test execution due to testing.execute=off exit 0 fi mpiexec.hydra -n 2 "../../../bin.v2/libs/mpi/test/broadcast_stl_test-2.test/intel-linux/debug/broadcast_stl_test-2" blob > "../../../bin.v2/libs/mpi/test/broadcast_stl_test-2.te st/intel-linux/debug/broadcast_stl_test-2-run.output" 2>&1 status=$? echo >> "../../../bin.v2/libs/mpi/test/broadcast_stl_test-2.test/intel-linux/debug/broadcast_stl_test-2-run.output" echo EXIT STATUS: $status >> "../../../bin.v2/libs/mpi/test/broadcast_stl_test-2.test/intel-linux/debug/broadcast_stl_test-2-run.output" if test $status -eq 0 ; then cp "../../../bin.v2/libs/mpi/test/broadcast_stl_test-2.test/intel-linux/debug/broadcast_stl_test-2-run.output" "../../../bin.v2/libs/mpi/test/broadcast_stl_test-2.test/intel- linux/debug/broadcast_stl_test-2-run" fi verbose=0 if test $status -ne 0 ; then verbose=1 fi if test $verbose -eq 1 ; then echo ====== BEGIN OUTPUT ====== cat "../../../bin.v2/libs/mpi/test/broadcast_stl_test-2.test/intel-linux/debug/broadcast_stl_test-2-run.output" echo ====== END OUTPUT ====== fi exit $status [alainm@gurney engine]$ ================================================= Note that select only test for the subprocess output, at the hanging point mpiexec.hydra is done with its outputs. Any idea ? Alain PS: there was a cmake based project some time ago, is it still active or is bjam here to stay ?

2 18

[Boost.Polygon] Union filling holes
by Julien Nicoulaud 27 Oct '14

27 Oct '14

Hi all, I am using boost/polygon to do unions of multiple polygons, and I lose holes that were in the input after the assign() operation. Here is code that demonstrates the issue: // Create outer contour Point outer[] = {gtl::construct<Point>(0, 0), gtl::construct<Point>(0, 10), gtl::construct<Point>(10, 10), gtl::construct<Point>(10, 0)}; // Create inner contour Point inner[] = {gtl::construct<Point>(2, 2), gtl::construct<Point>(8, 2), gtl::construct<Point>(8, 8), gtl::construct<Point>(2, 8)}; // Define inner contour as a polygon polygon_with_holes_data<long> input_poly_inner; gtl::set_points(input_poly_inner, inner, inner+4); // Put inner polygon in a list vector<polygon_with_holes_data<long> > inners; inners.push_back(input_poly_inner); // Create input polygon as outer contour + inner polygon list polygon_with_holes_data<long> input_poly; gtl::set_points(input_poly, outer, outer+4); gtl::set_holes(input_poly, inners.begin(), inners.end()); // Create input polygon set, insert input polygon polygon_set_data<long> input_poly_set; input_poly_set.insert(input_poly); // Create output polygon set, assign input polygon set vector<polygon_with_holes_data<long> > output_poly_set; assign(output_poly_set, input_poly_set); // Print result std::cout << output_poly_set.size() << " polys" << std::endl; std::cout << output_poly_set[0].size_holes() << " holes" << std::endl; This prints: 1 polys 0 holes Any idea what I am doing wrong ? Kind regards, Julien Nicoulaud

2 2

1.57.0 beta 1 is in a new location
by Marshall Clow 27 Oct '14

27 Oct '14

Tom Kent pointed out that I put the beta 1 files in a folder that we traditionally use for Windows binaries, so I have moved the beta files to https://sourceforge.net/projects/boost/files/boost/1.57.0.beta.1/ These are the same files as last Monday - merely in a new location. If you have already downloaded and tested the beta, thanks! - no need to do it again. — Marshall

1 0

[Geometry] Packing algorithm for r-tree?
by Jeremy Murphy 27 Oct '14

27 Oct '14

I see that a fourth node splitting algorithm for bulk loading is documented in the Introduction to spatial indexes but not listed elsewhere (such as Creation and Modification). Is it hiding in the library somewhere or is the introduction just a tantalizing sneak preview? Thanks, cheers. Jeremy

2 5

BGL, cut set
by Mads Jensen 27 Oct '14

27 Oct '14

Hi, I'm looking into how you can quickly find the cut set of a graph without having to loop over the colormap as a vector. I'm using the http://www.boost.org/doc/libs/1_56_0/libs/graph/doc/edmonds_karp_max_flow.h… (the example provided does mostly what I want, except that it uses a vector, and not a regular map). Boykov Kolmogorov also has the colormap parameter. It seems that associative_property_map could be used, but I don't really see how? Hints on how to do this will be appreciated. A lot of the examples of the Boost graph library use the preprocessor with a check similar to: #if defined(BOOST_MSVC) && BOOST_MSVC <= 1300 What's so special about this? Thank you, -- Med Venlig Hilsen / Kind regards, Mads Jensen

1 0

[Serialization] Deserialization of base class fails
by Torsten Wylegala 25 Oct '14

25 Oct '14

Hi, I'm currently trying to serialize and deserialize a derived class using boost::archive::xml_iarchive/xml_oarchive Version 1.52. Everything works fine as long as I serialize and deserialize the same class (Example 1). The attributes of the derived class and the base class are both serialized and the deserialized correctly and requestPackageOut equals requestPackageIn (the base-class attributes are equal too). But if I serialize the derived class "RequestPackage" and try to deserialize it into the base-class "Package" (Example 2) I'm getting an "input stream error" exception while trying to deserialize with ia >> BOOST_SERIALIZATION_NVP(*package);. I'm quite new to this topic and found a lot of posting but none of them seems to match and solve my exact problem. It would by very nice if somebody could help me with that. Background information: I want to use xml-serialized objects for data exchange via network and want all the packages to inherit from Package-class which carries "packageId" and therefore give me the chance to identify the incoming xml-objects and handle every package based on this id. If some information is missing I will do my best to provide it later. Torsten Example 1: int main(int argc, char** argv){ std::cout << "Started!" << std::endl; std::string serializedObject; RequestPackage requestPackageOut; RequestPackage requestPackageIn; requestPackageOut.setPackageId(3); requestPackageIn.setPackageId(0); Serializer::serialize(&serializedObject,&requestPackageOut); Serializer::deserialize(&serializedObject,&requestPackageIn); return 0; } Example 2: int main(int argc, char** argv){ std::cout << "Started!" << std::endl; std::string serializedObject; Package package; RequestPackage requestPackageOut; RequestPackage requestPackageIn; requestPackageOut.setPackageId(3); requestPackageIn.setPackageId(0); Serializer::serialize(&serializedObject,&requestPackageOut); Serializer::deserialize(&serializedObject,&package); return 0; } The Rest: namespace Serializer{ template <typename T> int serialize(std::string *serializedObject, T *package){ int returnValue = 0; std::ostringstream objectOss; boost::archive::xml_oarchive oa(objectOss); try { oa << BOOST_SERIALIZATION_NVP(package); } catch (boost::archive::archive_exception const& ex) { returnValue = 1; } serializedObject->assign(objectOss.str()); return returnValue; }; template <typename T> int deserialize(std::string *serializedObject, T *package){ int returnValue = 0; std::istringstream objectIss(*serializedObject); boost::archive::xml_iarchive ia(objectIss); try { ia >> BOOST_SERIALIZATION_NVP(*package); } catch (boost::archive::archive_exception const& ex) { std::cerr << "Error: " << ex.what() << std::endl; std::cerr.flush(); returnValue = 1; } return returnValue; }; } class RequestPackage : public Package{ private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(Package); ar & BOOST_SERIALIZATION_NVP(requestId); } int requestId; public: int getRequestId() const; void setRequestId(int requestId); }; class Package{ private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_NVP(packageID); } int packageID; public: int getPackageId() const; void setPackageId(int packageId); };

2 1

Boost Serialization
by Abraham, Marshel 25 Oct '14

25 Oct '14

I am trying to Serialize a class : StartPeerSessionRequest::StartPeerSessionRequest() { mProtocolVersion = 1*10000 + 14*100 + 4; mSessionFlags = 1; mMaxResponseLength = 0; mMake = "MyMake"; mModel = "MyModel"; mSerialNumber = "10000"; mTrackDelay = 0; mHeadUnitModel = "Headunit"; mCarModelYear = "2014"; mVin = "1234567980"; mVehicleMileage = 1000; mShoutFormat = 3; mNotificationInterval = 1; } template <class Archive> void StartPeerSessionRequest::serialize(Archive &ar, const unsigned int version) { ar & mProtocolVersion; ar & mSessionFlags; ar & mMaxResponseLength; ar & mMake; ar & mModel; ar & mSerialNumber; ar & mTrackDelay; ar & mHeadUnitModel; ar & mCarModelYear; ar & mVin; ar & mVehicleMileage; ar & mShoutFormat; ar & mNotificationInterval; } void StartPeerSessionRequest::save() { boost::archive::binary_oarchive oa(serlreq, boost::archive::no_header); oa << (*this); /*cout<<"\n binary_oarchive :"<<serlreq.size();*/ boost::archive::text_oarchive ota(serializedRequest, boost::archive::no_header); ota<<(*this); cout<<"\n text_oarchive :"<<serializedRequest.str()<<"size :"<<serializedRequest.str().size(); } serializedRequest.str.size() provides me a length of 87 actually it should provide me 65 bytes.( I ve counted u can figure that out from the constructor ) I suspect it is appending lengths in between. I have tried using text_archive also it doesnt work. What I need is to just plain serialize class members as it is. I guess i need to use some traits or wrappers, or boost::serialization::binary_object Please let me know Thanks Regards Marshel Abraham 3097146

2 2