December 2006 - Boost-users - lists.preview.boost.org

boost::cref behavior
by roblin＠jlab.org 07 Dec '06

07 Dec '06

Hi all, I was trying to understand the use of boost::ref and boost::cref and wrote this little snippet: #include <iostream> #include <boost/ref.hpp> #include <string> using namespace std; int main(int argc,char** argv) { boost::reference_wrapper<string const> ref=boost::cref(string("yoh")); const string das("bla"); const string & dasref=das; cout<<"das ref is "<<dasref<<endl; cout<<"ref is "<<ref.get()<<endl; return 0; } I am confused by what I get when I run this: das ref is bla ref is bla I was expecting: das ref is bla ref is yoh What am I doing wrong there ??

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Spamming through boost???
by Ovanes Markarian 07 Dec '06

07 Dec '06

Hi all! I give to all my opponents personalized email addresses, e.g. for boot my email is om_boost(a)domain_name.ext. Today I got my first spamming email to this address. Now I really think, there must be email servers inbetween, which simply log the sender and put them to the spamming lists. I don't see any other possiblity of how this can happen. I don't beleave that boost sells email addresses to spammers, after I know you guys. Would be nice to know what others think. I know that this email is off-topic, but can be useful anyway. With Kind Regards, Ovanes

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[Boost.Iostreams] does filtering_stream have a binary mode?
by Maurice van Swaaij 07 Dec '06

07 Dec '06

Hi, Is there a way to set a filtering_stream to binary mode so I can use its operator>> and operator<< to read and write binary data? Thanks. -- Maurice van Swaaij - Blue Sky Studios NY

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[BGL] read_graphviz
by Jeffrey Holle 06 Dec '06

06 Dec '06

I using the boost CVS version, obtained last week Tuesday. I'm interested in using read_graphviz in a fairly complex manner. I want to read multiple properties from a *.dot file, including: - 1 graph property - 2 vertex properties - 2 edge properties Can this be done with the read_graphviz? Moreover, I would like these properties to end up outside of the graph. If this is possible, how is it done?

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[date_time] how to parse "1/13/2006"
by Markus Werle 06 Dec '06

06 Dec '06

Hi! I have to read in a file format where the date is given as month/day/year, but without leading '0' for day and month. >From http://boost.org/doc/html/date_time/date_time_io.html I could not guess how to declare the facet format string (No leading zeroes required) Could you please complete the following code? std::istringstream iss; local_time_input_facet* input_facet = new local_time_input_facet(); ss.imbue(locale(ss.getloc(), input_facet)); input_facet->format("???????"); regards, Markus

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using source code files from boost-sandbox
by Luca Cappa 06 Dec '06

06 Dec '06

Hello, I would like to use the circularbuffer class provided by boost-sandbox, and I would be glad if someone could tell me which are the rules to include the boost-sandbox files (either the .cpp and the .h) in my building process, i.e. should I copy only the relevant files into the actual boost installation directory, or anything else? Luca

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Re: [Boost-users] Binding to an overloaded member function
by Javier Estrada 05 Dec '06

05 Dec '06

Excellent. Thx. I knew it was somewhere in the documentation (Boost 1.33) but I could not get my hands around it ;-) -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Sebastian Redl Sent: Tuesday, December 05, 2006 1:20 PM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] Binding to an overloaded member function Javier Estrada wrote: > How can I use boost bind to bind to an overloaded member function? > You have to cast explicitly to select the correct overload. > But when I added: > > void C::dial(char key, MyConstants c); void C::dial(string toDial); > void C::dial(string, MyConstants c); > > References to my working code break: > > for_each(begin, end, boost::bind(&C::dial, this, _1 )); > for_each(begin, end, boost::bind( static_cast<void (C::*)(char)>(&C::dial), this, _1)); Sebastian Redl _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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Binding to an overloaded member function
by Javier Estrada 05 Dec '06

05 Dec '06

How can I use boost bind to bind to an overloaded member function? I had working code for a member function: void C::dial(char key); But when I added: void C::dial(char key, MyConstants c); void C::dial(string toDial); void C::dial(string, MyConstants c); References to my working code break: for_each(begin, end, boost::bind(&C::dial, this, _1 )); Regards, Javier

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Boost-users Digest, Vol 1107, Issue 3 (fwd)
by Mark Ruzon 05 Dec '06

05 Dec '06

>On Dec 4, 2006, at 6:28 PM, Mark Ruzon wrote: > >> The documentation for tuple says there are no portability problems >> with >> gcc 2.95. I am using 3.2.3 and am getting a syntax error on the >> line that >> does the work of this function object: >> >> #include <boost/tuple/tuple.hpp> >> >> struct get_0_func { >> template <typename II> // II models Input Iterator on tuple >> void operator()(II it) { it->get<0>(); } > >try : > > void operator()(II it) { it->template get<0>(); } > >Not tested, but this is likely the reason. The compiler does not how >yo parse < between get and 0, if not told >that get is a template. > > Jaakko J?rvi Thank you, Jaakko, this works fine. How do I get the documentation for tuple amended to include this form? Mark

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[iostreams] How to strip off checksum at end of file in multichar input filter?
by eg 05 Dec '06

05 Dec '06

Hi all, I've written a multichar_dual_use_filter for to handle a custom file encryption. Ideally, the encrypted file format consists of 3 distinct types of data: 1) initialization vector IV (only used by encry/decryp) 2) Main file data 3) Checksum (only used to validate file decryp is correct) The output filter can easily write the above 3 items. I have the input filter reading in and handling items 1 and 2 above... But I need some advice on how to strip off the checksum (or any fixed size chunk of data) at the end of the file to validate but not pass this into the output buffer. I have thought of passing in the input file size to the filters constructor and keep track of how many bytes are being processed... then handling the final bytes separately. Does this sound like a feasible approach? It makes using the filter harder as it imposes unusual constraints on calling it. Any other ideas? My current filters Read function is of the following form: template<typename Source> std::streamsize read(Source& src, char* s, std::streamsize n) { if (!bInit) { // Handle reading IV bytes and initialization } // Read in buffer to "s" and then decrypt it count = boost::iostreams::read(src, s, n); if (count <= 0) return -1; //EOF or Error // Decrypt s in place DecryptBuf(s, count); return count; }

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