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How to use boost::thread::sleep(...)?
by Jean-Sebastien Stoezel 05 Jul '08

05 Jul '08

Hi, I would like to relinquish the CPU from a thread so I thought using boost::thread::sleep(...). However, I have no idea how to initialize its argument. It looks like this is a boost::system_time. How to initiliaze such a type so my thread waits 20ms, 100ms...!? Thanks!

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[Threads] how to cross-compile boost.threads from cygwin to target win32?
by frederic.bron＠alcan.com 05 Jul '08

05 Jul '08

I have been using boost with success since 1 year on the following systems: 1) cygwin built with cygwin gcc/g++, 2) win32 built with cygwin gcc/g++ with -mno-cygwin flag, 3) linux built with both gcc/g++ or intel compiler. I now want to use boost.threads and I have discovered that the library was not automatically built for system 2), i.e. win32. How can I force bjam to compile for the target win32 using windows threads instead of cygwin pthread? It seems that there are some bjam options like target-os and threadapi but I could not get any documentation for it. What is the list of possible target-os or threadapi values? Regards, F. Bron Avis : Ce message et toute pièce jointe sont la propriété d'Alcan et sont destinés seulement aux personnes ou à l'entité à qui le message est adressé. Si vous avez reçu ce message par erreur, veuillez le détruire et en aviser l'expéditeur par courriel. Si vous n'êtes pas le destinataire du message, vous n'êtes pas autorisé à utiliser, à copier ou à divulguer le contenu du message ou ses pièces jointes en tout ou en partie. Notice: This message and any attachments are the property of Alcan and are intended solely for the named recipients or entity to whom this message is addressed. If you have received this message in error please inform the sender via e-mail and destroy the message. If you are not the intended recipient you are not allowed to use, copy or disclose the contents or attachments in whole or in part.

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BOOST_DYN_LINK
by Johan Råde 05 Jul '08

05 Jul '08

I'm using Boost 1.35 with VC 9.0 on Windows XP. I just tried to link dynamically with Boost. So I added #define BOOST_DYN_LINK to the first line of each StdAfx.h file. When the app links, I get the error message: LINK : fatal error LNK1104: cannot open file 'libboost_serialization-vc90-mt-gd-1_35.lib' It is trying to link with the static libraries. So I decided to take a look in the Boost docs. Well, I could not find anything anywhere about BOOST_DYN_LINK. How do I link dynamically with Boost, using the auto-link mechanism? Is BOOST_DYN_LINK the right way? --Johan

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shared_ptr invalid covariant return type
by John 05 Jul '08

05 Jul '08

This pattern/idiom is well-established: struct A { virtual A* clone () = 0; }; struct B : public A { virtual B* clone (); }; But the above does not work when the pointers A* and B* are replaced by shared_ptr<A> and shared_ptr<B>: struct A { virtual shared_ptr<A> clone () = 0; }; struct B : public A { virtual shared_ptr<B> clone (); }; Is there a workaround? Another way to solve the same problem? Thanks! -John

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Boost::Multi_array and reducing dimensions
by Joey Mukherjee 04 Jul '08

04 Jul '08

I am trying to use boost::multi_array and want to create a view where I am lowering the number of dimensions, but I wish the dimension to be reduced to be decided at runtime. I have a vector of integers and this vector size is the same as the number of dimensions. If the vector [1] value is -1, then the first dimension will have all values (i.e. range ()), otherwise it will be a number indicating what slice to use. You can see in case 2 what I have tried and maybe what I am trying to do. Case 3 and 4 I am hard coding the dimensions where I want all values, which does work, but I'd like to get rid of the hard-codedness and make this more generic. Furthermore, I have a one dimensional array of values which I am "converting" to a boost::multi_array so I can slice into it with the views. I won't know the dimensions until I read the data. Is there a better more generic way of doing this? Something like a pointer to a N-dimensional structure where I can just use the view? Thanks in advance for any ideas! Joey Here is my code: { double ret_val; typedef boost::multi_array_types::index_range range; const VariableInfo &vinfo = GetVariable (si._sensor); SubSensorType local_subsensors (si._subsensors); assert (local_subsensors.size () == vinfo._sizes.size ()); switch (vinfo._sizes.size ()) { case 0 : ret_val = vals [0]; break; case 1 : { // one-d array ret_val = (vals [whichPosition]); } break; // Now we get into slices, find the subsensor element that has -1, and // create a slice along that dimension case 2 : { // two-dimensional array typedef boost::const_multi_array_ref <double, 2> array_type; array_type::index_gen indices; array_type multi_array (&(vals [0]), vinfo._sizes); /* This doesn't work! array_type::const_array_view <1>::type OneDView; if (local_subsensors [0] == -1) OneDView = multi_array [indices [range ()] [local_subsensors [1]]]; else if (local_subsensors [1] == -1) OneDView = multi_array [indices [local_subsensors [0] [range ()]]]; ret_val = (OneDView [whichPosition]); */ } break; case 3 : { // three-dimensional array typedef boost::const_multi_array_ref <double, 3> array_type; array_type::index_gen indices; array_type multi_array (&(vals [0]), vinfo._sizes); array_type::const_array_view <1>::type OneDView = multi_array [indices [local_subsensors [0]] [local_subsensors [1]] [range ()]]; ret_val = (OneDView [whichPosition]); } break; case 4 : { // four-dimensional array typedef boost::const_multi_array_ref <double, 4> array_type; array_type::index_gen indices; array_type multi_array (&(vals [0]), vinfo._sizes); array_type::const_array_view <1>::type OneDView = multi_array [indices [local_subsensors [0]] [local_subsensors [1]] [local_subsensors [2]] [range ()]]; ret_val = (OneDView [whichPosition]); } break; default : assert (vinfo._sizes.size () < 4); } return (ret_val);

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[serialization] priority_queue
by mbrodeur65 04 Jul '08

04 Jul '08

Hi, I am wondering if there is a way to serialize a std::priority_queue ? thanks for any help. -- View this message in context: http://www.nabble.com/-serialization--priority_queue-tp18239627p18239627.ht… Sent from the Boost - Users mailing list archive at Nabble.com.

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bjam: defining string literals HELP!!!!
by jono 04 Jul '08

04 Jul '08

hi, it would be really useful for me to be able to define a string literal in a Jamfile... eg: ===================================================== dll useful_variant : <template>useful src/modules/interpreter/useful_variant.cpp : # requirements <define>VARIANT <define>NAME="variant" ; ===================================================== gcc -DNAME=\"variant\" does what i want, so i've also tried <cxxflags>-DMODULENAME="variant" <cxxflags>"-DMODULENAME="variant"" <cxxflags>'-DMODULENAME="variant"' <cxxflags>"-DMODULENAME=\"variant\"" <cxxflags>"-DMODULENAME=\"\"variant\"\"" <cxxflags>"-DMODULENAME=""variant""" and various other hopeful monsters... but whatever i do, 'variant' appears in the source file as an identifier not a string. is it possible to achieve what i want with bjam??????????????????????????? cheers, and thanks in advance. Jono day-one.com

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[Boost.Bind] Adding a single argument to an existing function, breaks the code.
by Vjekoslav Brajkovic 04 Jul '08

04 Jul '08

Hi. I am experiencing some issues with boost::bind and I was hoping if anybody is willing to help me. The example is really simple: First I have a function: void com_client::handle_init( const std::string& host, const command_t command) { boost::asio::ip::tcp::resolver resolver(connection_.socket().io_service()); boost::asio::ip::tcp::resolver::query query(host, service_); boost::asio::ip::tcp::resolver::iterator endpoint_iterator; endpoint_iterator = resolver.resolve(query); boost::asio::ip::tcp::endpoint endpoint = *endpoint_iterator; connection_.socket().async_connect(endpoint, boost::bind( &com_client::handle_connect, this, 2, boost::asio::placeholders::error, ++endpoint_iterator) ); } After successful handshake, this function is called: void com_client::handle_connect( command_t command, const boost::system::error_code& e, boost::asio::ip::tcp::resolver::iterator endpoint_iterator) { if (!e) { rLog(com_client_control_, "Connection established with remote end-point %s.", connection_.socket().remote_endpoint().address().to_string().c_str()); command_ = DEPOSIT_CHUNK; connection_.async_write(command_, boost::bind( &com_client::handle_write_cmd, this, boost::asio::placeholders::error) ); } else if (endpoint_iterator != boost::asio::ip::tcp::resolver::iterator()) { connection_.socket().close(); boost::asio::ip::tcp::endpoint endpoint = *endpoint_iterator; connection_.socket().async_connect(endpoint, boost::bind( &com_client::handle_connect, this, boost::asio::placeholders::error, ++endpoint_iterator)); } else { std::cerr << e.message() << std::endl; } } This issue is when I modify the code such that connection_.socket().async_connect(endpoint, boost::bind( &com_client::handle_connect, this, //2, boost::asio::placeholders::error, ++endpoint_iterator) ); void com_client::handle_connect( //command_t command, const boost::system::error_code& e, boost::asio::ip::tcp::resolver::iterator endpoint_iterator) { one of the arguments is removed code compiles. And also: enum command_t { DEPOSIT_CHUNK = 2, DETRIEVE_CHUNK = 4, HEARTBEAT = 16 }; I was hoping if somebody could explain this. I've attached g++ output. -V

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Creating new operators & function under proto
by Joel FALCOU 03 Jul '08

03 Jul '08

Hi, I tried follwoing the tutorial to create new functions to use in Proto but it failed. Let's say I want to have a new unary function called worker that create an expression that ought to be matched by the following grammar : struct worker_grammar : or_< terminal< user_func<_> >, function< worker_tag, terminal< user_func<_> > > {}; I keep getting a 'no type named proto_expr_base in worker_tag' error. Related question, how can I make a new function which tag is a tempalte class whose tempalte parameter is used to change how the associated transform is performed, I tried : struct worker_grammar : or_< terminal< user_func<_> >, function< worker_tag<_>, terminal< user_func<_> > > {}; but it failed too. Thanks in advance -- Joel FALCOU Research Engineer @ Institut d'Electronique Fondamentale Université PARIS SUD XI France

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1_36 serialization... another issue...
by Mathieu Peyréga 03 Jul '08

03 Jul '08

Following my previous post... it seems that there are issues with xml too... the 1_35 saved file does not load with 1_36 framework... it seems that the "missing" <item_version>0</item_version> makes the difference.... I hope that may help the developpers... in case i did not misuse the library... Regards, Mathieu -- http://www.incub.net/

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