#include <stdlib.h>
#include <stdio.h>
#include <string>
#include<iostream>
 #include<fstream>
#include<vector>

using namespace std;

class kontaktlist
{
public:
ifstream is;
ofstream off;

	kontaktlist(char* begin,char *neu) {
 		readlist(begin);
   		writelist(begin,neu);
  		clearlist(begin,neu);
	}

	vector<string> readlist (char *begin){
	        vector<string>foo_r;
	        string end=".c";
	        string all = begin + end;
	  	char *next_r = &all.at(0);
		is.open(next_r,ios::in);
		  if (is.is_open())
		  {
			is.seekg (0, ios::end);
  		  	int length_r = 0;
		  	length_r = is.tellg();
  		  	is.seekg (0, ios::beg);
		  	char *buffer_r = new char[length_r];
			is.read (buffer_r,length_r);
		  	is.close();
			foo_r.push_back(buffer_r);
			return (foo_r);
		  	}else{
			is.close();
			off.open(next_r,ios::out|ios::app);
			off<<"";
			off.close();
			return (foo_r);
		}
	}

	void writelist (char *begin,string neu){
		string end=".c";
	        string all = begin + end;
	  	char *next_w = &all.at(0);
	    	is.open(next_w,ios::in);
		if (is.is_open())
  		{
			is.close();
			off.open(next_w,ios::out|ios::app);
    			neu= neu + ';';
		    	char *neu_w = &neu.at(0);
			off<<neu_w;
    			off.close();
  		}else{
			is.close();
			off.open(next_w,ios::out|ios::app);
			off<<"";
			off.close();
		}
	}

	void clearlist(char *begin_c,char *name){
		int i=0;
		int anz=0;
		string end_c =".c";
		string all_c = begin_c + end_c;
		char *next_c = &all_c.at(0);
		is.open(next_c,ios::in);
		if(is.is_open()){
			is.seekg (0, ios::end);
  			int length_c = 0;
			length_c = is.tellg();
			char vor[length_c];
  			is.seekg (0, ios::beg);
			//Abfangschleife:Datei ist leer
			if(length_c==0)
			{
				is.close();
			}else{
				char *buffer_c = new char[length_c];
				is.read (buffer_c,length_c);
				memcpy(vor,buffer_c,length_c);
				for(int k= 0;k<length_c;k++)
				{
					if(vor[k]==';')
					{
						anz++;
					}
				}
				string foo_c[anz];
				for(int h= 0;h<length_c-1;h++)
				{
					if(vor[h]==';')
					{
						i++;
					}else{
						foo_c[i] +=vor[h];
					}

			 	}
				bool kontr= false;
				for(int j=0;j<i;j++)
				{
				  	if(foo_c[j]== name)
					{
						for (int l=j; l<i;l++)
				    		{
							foo_c[l]=foo_c[l+1];
						}
					kontr=true;	
					}
				}
				//Kontrallschleife: eigegebener Benutzer existiert nicht in der Kontaktliste
				if(kontr== false)
				{
					is.close();
				}else{
				 	is.close();
				 	off.open(next_c,ios::out);
				 	for(int l= 0;l<i-1;l++)
					{
				 		off<<foo_c[l];
						off<<';';
				 	}
				 	off.close();
				}
			}
		}else{
			//Datei existiert nicht und wirde deshalb erzeugt
			is.close();
			off.open(next_c,ios::out|ios::app);
			off<<"";
			off.close();		
		}
	}

};
 int main(){
    kontaktlist test("cat","hallo");
    return 0;
 }

versucht in eine Libary umzuwandeln:
siehst du hier:
http://www.rafb.net/paste/results/5lT5mF57.html
hab ich das so richtig gemacht?? (ist mein first try)
bitte um Antworten.Thx.