From: ruben safir <ruben@mrbrklyn.com>
Newsgroups: comp.lang.c++
Subject: fstream - clobbering
Date: Mon, 6 Jun 2011 08:16:08 +0000 (UTC)
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.c++:6264

I'm trying to figure out why the data file seems to be clobbered




 void Deck::add_questions(Question &enter){
	   //open file
	   Deck tmp;
	   std::ofstream all_quest( tmp.database.c_str(), std::ios::binary );
	   if(!all_quest){
	     std::cerr << "can't open question database for writing" << std::endl;
	     exit(1);
	   }
	   all_quest.seekp( 0, std::ios_base::end);
	   std::cout << "value of enter.quest ============> \n\n" << enter.quest << "Size of string\n" << sizeof(char) *enter.quest.size()  << std::endl;
	   all_quest.write(enter.quest.c_str(), sizeof(char) * enter.quest.size() );
	   all_quest.write(enter.answer.c_str(), sizeof(char) * enter.answer.size() );
	   all_quest.close();
	   return;
	   
   }




I don't think that std::ios::binary clobbers the file and  
all_quest.seekp( 0, std::ios_base::end);

should be setting the the put pos at the end of the file.


Ruben