Subj : istream& getline (istream& is, string& str, char delim = '\n');
To   : borland.public.cpp.borlandcpp
From : Maya <EscalanteCanada@netscape.net>
Date : Tue Oct 28 2003 01:55 pm

Question: Help using ' istream& getline (istream& is, string& str, char 
delim = '\n'); '




First of all, I apologize I am addressing this question to the wrong 
mail_list/news_group. If so, please just disregard this message.
Here is my problem:
The below overloaded extractor is not the only one in my class. There is 
an overloaded extractor for all the primitive data types as  well as for 
std::string objects.
All of inserters and extractors handling primitive data types are 
identical, the only difference is that each handles different data 
types. However, the overloaded operator handling std::string objects is 
giving me some strange behavior.
Staring with the data in the file stream and continuing with a sip of 
the source code, let me show you what it is that I am talking about.

-- data in the file stream is: --
Where are the weapons of mass destruction? Sir.^
-- snip --
virtual std::string& operator>>(std::string& data)
throw(jme::CursorPosition, jme::StreamEx, std::bad_alloc){
   /** Set the position of the file get pointer,  if there are any 
errors  throw an exception explaining what when wrong **/
   try{setNextRead();}
   catch(jme::CursorPositionEx& x){throw;  }
   catch(jme::StreamEx& x) {throw; }

   /** Make sure that there is data to be read in the file**/
   if(file_is_empty()){  throw io_baseEx(FE_EMPTY,FILE,METHOD,LINE);}

   /**  set the file's cursor position the the value returned by 
getNextRead(), which will never be < zero **/
   f.seekg( getNextRead());

   /** Get the a string from of character from the file stream until "^" 
is found **/
   std::getline(f,data,'^')
//Testing
std::cout << "Data is: " << data << std::endl; <<== Displays the right 
string value
std::cout << "Current Cursor Pos " << f.tellg() << std::endl;  //<== 
Returns -1; an error??
std::cin.get();
//End testing
   try{setNextRead();}
   catch(jme::CursorPosition& x){ throw;  }
   catch(jme::StreamEx& x){throw;  } <== because ftellg is -1 this 
exception is thrown
    f.sync();
    return data;
}
Again, thanks folks for the help!
-- 

Jorge Escalante
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