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BOOST_PP_STRINGIZE for wchar_t?
by Hansi 09 Mar '09

09 Mar '09

Hello, is there any equivalent preprocessor macro available for BOOST_PP_STRINGIZE which gets a L"string"? Thanks Hansjörg

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[asio] reopening of serial port fails - why?
by Markus Werle 09 Mar '09

09 Mar '09

Hi! The code below perfectly reads characters from the serial line for 6 seconds. The termination of the thread and a reopening of the connection then fails. What am i missing here? Markus ---snip--- // TestBoostAsio.cpp : Defines the entry point for the console application. // #include "stdafx.h" //int _tmain(int argc, _TCHAR* argv[]) //{ // return 0; //} /* minicom.cpp A simple demonstration minicom client with Boost asio Parameters: baud rate serial port (eg /dev/ttyS0 or COM1) To end the application, send Ctrl-C on standard input */ #include <deque> #include <iostream> #include <boost/bind.hpp> #include <boost/asio.hpp> #include <boost/asio/serial_port.hpp> #include <boost/thread.hpp> #include <boost/lexical_cast.hpp> #include <boost/date_time/posix_time/posix_time_types.hpp> #include <iostream> #ifdef POSIX #include <termios.h> #endif using namespace std; class minicom_client { public: minicom_client(boost::asio::io_service& io_service, unsigned int baud, const string& device) : active_(true), io_service_(io_service), serialPort(io_service, device) { if (!serialPort.is_open()) { cerr << "Failed to open serial port\n"; return; } boost::asio::serial_port_base::baud_rate baud_option(baud); serialPort.set_option(baud_option); // set the baud rate after the port has been opened read_start(); } void write(const char msg) // pass the write data to the do_write function via the io service in the other thread { io_service_.post(boost::bind(&minicom_client::do_write, this, msg)); } void close() // call the do_close function via the io service in the other thread { io_service_.post(boost::bind(&minicom_client::do_close, this, boost::system::error_code())); } bool active() // return true if the socket is still active { return active_; } private: static const int max_read_length = 512; // maximum amount of data to read in one operation void read_start(void) { // Start an asynchronous read and call read_complete when it completes or fails serialPort.async_read_some(boost::asio::buffer(read_msg_, max_read_length), boost::bind (&minicom_client::read_complete, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); } void read_complete(const boost::system::error_code& error, size_t bytes_transferred) { // the asynchronous read operation has now completed or failed and returned an error if (!error) { // read completed, so process the data cout.write(read_msg_, bytes_transferred); // echo to standard output read_start(); // start waiting for another asynchronous read again } else do_close(error); } void do_write(const char msg) { // callback to handle write call from outside this class bool write_in_progress = !write_msgs_.empty(); // is there anything currently being written? write_msgs_.push_back(msg); // store in write buffer if (!write_in_progress) // if nothing is currently being written, then start write_start(); } void write_start(void) { // Start an asynchronous write and call write_complete when it completes or fails boost::asio::async_write(serialPort, boost::asio::buffer(&write_msgs_.front(), 1), boost::bind (&minicom_client::write_complete, this, boost::asio::placeholders::error)); } void write_complete(const boost::system::error_code& error) { // the asynchronous read operation has now completed or failed and returned an error if (!error) { // write completed, so send next write data write_msgs_.pop_front(); // remove the completed data if (!write_msgs_.empty()) // if there is anthing left to be written write_start(); // then start sending the next item in the buffer } else do_close(error); } void do_close(const boost::system::error_code& error) { // something has gone wrong, so close the socket & make this object inactive if (error == boost::asio::error::operation_aborted) // if this call is the result of a timer cancel() return; // ignore it because the connection cancelled the timer if (error) cerr << "Error: " << error.message() << endl; // show the error message else cout << "Error: Connection did not succeed.\n"; cout << "Press Enter to exit\n"; serialPort.close(); active_ = false; } private: bool active_; // remains true while this object is still operating boost::asio::io_service& io_service_; // the main IO service that runs this connection boost::asio::serial_port serialPort; // the serial port this instance is connected to char read_msg_[max_read_length]; // data read from the socket deque<char> write_msgs_; // buffered write data }; int main(int argc, char* argv[]) { // on Unix POSIX based systems, turn off line buffering of input, so cin.get() returns after every keypress // On other systems, you'll need to look for an equivalent #ifdef POSIX termios stored_settings; tcgetattr(0, &stored_settings); termios new_settings = stored_settings; new_settings.c_lflag &= (~ICANON); new_settings.c_lflag &= (~ISIG); // don't automatically handle control- C tcsetattr(0, TCSANOW, &new_settings); #endif try { if (argc != 3) { cerr << "Usage: minicom <baud> <device>\n"; return 1; } boost::asio::io_service io_service; // define an instance of the main class of this program minicom_client c(io_service, boost::lexical_cast<unsigned int> (argv[1]), argv[2]); // run the IO service as a separate thread, so the main thread can block on standard input while (true) // PROBLEM: reentering this loop fails - why? { boost::thread t(boost::bind (&boost::asio::io_service::run, &io_service)); boost::asio::io_service io; boost::asio::deadline_timer timer(io, boost::posix_time::seconds(3)); timer.wait(); c.write('a'); boost::asio::deadline_timer timer2(io, boost::posix_time::seconds(3)); timer2.wait(); //while (c.active()) // check the internal state of the connection to make sure it's still running //{ // char ch; // cin.get(ch); // blocking wait for standard input // if (ch == 32) // ctrl-C to end program // break; // c.write(ch); //} c.close(); // close the minicom client connection t.join(); // wait for the IO service thread to close std::cout << "-------------------" << std::endl; } } catch (exception& e) { cerr << "Exception: " << e.what() << "\n"; } #ifdef POSIX // restore default buffering of standard input tcsetattr(0, TCSANOW, &stored_settings); #endif return 0; }

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[Unordered] template find() request
by Kenneth Heafield 09 Mar '09

09 Mar '09

Hello Boost, Suppose I have a boost::unordered_set<std::string>. Now I want to find() a const char *, std::string, or even a string without zero termination (Google StringPiece). Converting these to std::string just to do a lookup is wasteful. Instead, I want to provide functors like: struct either_hash { size_t operator()(const std::string &str) const { return boost::hash_range(str.begin(), str.end()); } size_t operator()(const char *str) const { return boost::hash_range(str, str + std::strlen(str)); } }; This raises the question: what is either_hash::argument_type ? But it seems this is not used by boost::unordered_set . It should probably be std::string to match the underlying hash table. Would it make sense to change find() to template <class query_type> const_iterator find(const query_type& q) const ? For those familiar with Google StringPiece, one solution is using boost::unordered_set<StringPiece>, but then I have to keep the underlying strings somewhere outside the table. Further, a generalized find is useful in other cases, but this was the easiest to explain. Kenneth

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Using program_options from a string?
by boostnewbie 09 Mar '09

09 Mar '09

Hello all. I am using the boost::program_options library for configuration files with great success. I'm wondering if it's possible to use the library using a string as a source, instead of a config file. I read the configuration file with code like this: if (vm.count("config")) { string f = vm["config"].as<string>() ; ifstream ifs(f.c_str()); store(parse_config_file(ifs, config_file_options), vm); po::notify(vm); } but what I'd also like to do is something along these lines, with a string as the original source instead of a file specified with my 'config' command line option: string str = "port = 3000 \n tmpdir = /tmp \n"; // something like this. this is what's in the config file. istringstream iss(str, istringstream::in); store(parse_config_file(iss, config_file_options), vm); po::notify(vm); These lines compile and execute without error but don't actually appear to update the 'vm'. Am I doing something wrong or is this not possible with the current incarnation of program_options? Thanks! -- View this message in context: http://www.nabble.com/Using-program_options-from-a-string--tp22405416p22405… Sent from the Boost - Users mailing list archive at Nabble.com.

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lexical_cast<unsigned char>: Compiler error
by Hansi 09 Mar '09

09 Mar '09

Hello, I have a question. I need a lexical_cast for a BYTE. Now I get allways a compile error with VS2005 and VS2008: e.g. unsigned char test = 2; test = boost::lexical_cast<unsigned char>(L"2"); Error 2 error C2679: binary '>>' : no operator found which takes a right-hand operand of type 'unsigned char' (or there is no acceptable conversion) D:\boost\boost_1_38_0\boost\lexical_cast.hpp 771 What I do wrong? How I can solve this problem? Regards Hansjörg

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Does boost have something like this, or does it need one?
by Roberto Gimenez 08 Mar '09

08 Mar '09

I need something like this: template <typename Type> struct Array { private: Type *data; int size; public: explicit Array(Type *data, int size) : data(data), size(size) { assert(size > 0); } Type &operator[](int index) const { return data[index]; } Type &at(int index) const { assert(index > 0 && index < size); return data[index]; } Type *getData() const { return data; } Type *begin() const { return data; } Type *end() const { return data + size; } int getSize() const { return size; } }; But I think boost doesn't have it. boost::array also takes an std::size_t template parameter but that doesn't work for what I want to do because I want to be able to pass a function something like this: void myFunction(const Array<int> &a) { ... } void main() { int myVec1[6] = { 1,2,3,4,5,6 }; int myVec2[2] = { 7,8 }; myFunction(Array<int>(myVec1, 6)); myFunction(Array<int>(myVec2, 2)); } I can't do this with boost::array and std::vector allocates and I don't want that too. Any help?

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[serialization] nans and infinite floats in text based archives...
by François Mauger 08 Mar '09

08 Mar '09

Hi serializers, archivers, boosters and Robert, I've used boost:serialization (boost 1.34.1 under Linux ubuntu and/or SL4,, gcc 4.2) for one year. Thanks to this excellent library, our team store critical experimental data (3 TB using zipped text archives). Up to now, I met no problem with text/XML archives as all the stored double values pass the 'isnormal' check. Now my new data analysis programs needs to (de)serialize doubles even if they are NaNs or infinites (for it makes sense for me). Unfortunately, the load method for double fails while reading 'nan' (or 'inf') from the input for this is the standard behavior of the ostream with "! isnormal" doubles. After studying the source code for boost text oriented I/O archives in the hope to find a fix for my problem, I made an attempt to make boost aware of nans and +/-infs in a pragmatic way (I mean trying to save time and storage but keep the information and get rid of the stream error exception). I attached a tiny tarball to show the hack I've done. I'm not sure at all this is be a definitively good and elegant approach to handle nans within text based archives. So I'd appreciate to get some feedback and comments from Robert or any expert in this field. As I work only with Linux, gcc and 1.34.1, this approach is likely not to be portable... but maybe this could initiate some work to fix it in an official way. thanks for your attention and for all this very very useful material. regards frc -- Francois Mauger Laboratoire de Physique Corpusculaire de Caen et Universite de Caen ENSICAEN - 6, Boulevard du Marechal Juin, 14050 CAEN Cedex, FRANCE e-mail: mauger(a)lpccaen.in2p3.fr tel.: (0/+33) 2 31 45 25 12 fax: (0/+33) 2 31 45 25 49

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Re: [Boost-users] [Proto] Annoying MSVC bug
by Vial, Florent 08 Mar '09

08 Mar '09

>> I'd like to encourage Microsoft to reopen this bug report and fix it. >> Could any of you with logins to Microsoft Connect go here >> https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?Fe edbackID=282942 >> and answer their 3 question survey expressing your dissatisfaction and >> encourage them to fix this. For those lazy not wanting to browse back like i did: the connect ID is 282942. >https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?F eedbackID=283021 And here 283021. Cheers, Florent Arnold & Richter Cine Technik GmbH & Co. Betriebs KG Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRA 57918 Personlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRB 54477 Geschaftsfuhrer: Prof. Dr. Dejan Ilic; Franz Kraus; Jens Schafer

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[mem_fn] Ambiguous call to mem_fn with stdcall function
by Conrad Scott 08 Mar '09

08 Mar '09

I'm trying to use g++ (and MinGW) to compile a win32 Direct3X program that I've written under Visual C++. All is well (so far) except for one thing. I'm using the technique suggested in the Boost shared_ptr documentation to store pointers to COM objects, which works fine under Visual C++ but under g++ (either 3.4.x or 4.3.x) I get errors about the call to mem_fn being ambiguous due to stdcall / non-stdcall overloading. I can't find any references to this problem on the net so I assume I'm doing something utterly boneheaded. Any hints would be very welcome. For example: #define BOOST_MEM_FN_ENABLE_STDCALL #include <d3d9.h> #include <boost/mem_fn.hpp> #include <boost/shared_ptr.hpp> void test_mem_fn(IDirect3DDevice9 * const device) { boost::shared_ptr<IDirect3DDevice9> ptr( device, boost::mem_fn(&IDirect3DDevice9::Release) ); } test/test_mem_fn.cpp:13: error: call of overloaded 'mem_fn(ULONG (IDirect3DDevice9::*)())' is ambiguous C:/Boost/include/boost-1_38/boost/bind/mem_fn_cc.hpp:15: note: candidates are: boost::_mfi::mf0<R, T> boost::mem_fn(R (T::*)()) [with R = ULONG, T = IDirect3DDevice9] C:/Boost/include/boost-1_38/boost/bind/mem_fn_cc.hpp:15: note: boost::_mfi::mf0_stdcall<R, T> boost::mem_fn(R (T::*)()) [with R = ULONG, T = IDirect3DDevice9] C:/Boost/include/boost-1_38/boost/mem_fn.hpp:382: note: boost::_mfi::dm<R, T> boost::mem_fn(R T::*) [with R = ULONG ()(), T = IDirect3DDevice9] Many thanks, Conrad

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Options for --build-type
by Juan D Guzman 07 Mar '09

07 Mar '09

I'm building boost and was wondering other than --build-type=complete what are the other options. Disk usage approaches 40 gigs with the complete option.

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