record_node *position_insertion_point(char lastname[50])
{
	record_node *temp_ptr = 0;

	if( head_ptr->next == 0 ) return head_ptr;
	if( strcmp(lastname,head_ptr->next->last_name) < 0 ) return head_ptr; // insert after head

	temp_ptr = head_ptr->next;
	while( temp_ptr->next != 0 )
	{
		if( strcmp(lastname,temp_ptr->next->last_name) < 0 ) return temp_ptr; // insert after temp
		temp_ptr=temp_ptr->next;
	}
	return temp_ptr; // insert at end
}

#ifndef _DATABASE_HPP_
#define _DATABASE_HPP_

#include<list>
#include<string>
#include<iostream>
#include<algorithm>
#include<iterator>

//#include<fstream>


namespace database_io{


// example data class 
class userdata{
	friend const bool operator<(const userdata&,const userdata&);
	friend const bool operator==(const userdata &,const userdata &);
	friend std::ostream& operator<<(std::ostream &,const userdata &);
public:
	explicit userdata(const std::string&n ,const std::string &ln,const std::string &mail, const int &a):name_(n),last_name_(ln),email_(mail),age_(a){}
	
private:
	std::string name_;
	std::string last_name_;
	std::string email_;
	short int age_;
};


/*********************
right now i'm too lazy wo write a save load function, since this is another special case..(for the 
userdata class only)... 
a way to on my mind to do it : 
read:
1 define a max size per string and an delimiter ( shouldnt be ' ' ) then use getline  in a loop 
"while(!your_ifsream.eof()) to read the strings and the age and then use userdata_factory to insert it... and so on...
write
also use the max size and the same delimiter and std::string.c_str() for example than just write.... 
maybe this isnt the best way but its of course one way to make it 
**************/



// this one is like yours because this functions aint important at all 
// because it handles just the specific case userdata
const userdata userdata_factory(){
	using std::cin;
	using std::cout;
	std::string n,ln,mail;
	int age;

	cin.ignore(80,'\n');
	cout<<"\nNEW RECORD\n";
	cout<<"\n";
	cout<<"First Name: ";
	cin>>n;
	cin.ignore(80,'\n');
	cout<<"Last Name: ";
	cin>>ln;
	cin.ignore(80,'\n');
	cout<<"Email Address: ";
	cin>>mail;
#ifdef _VALIDATE_EMAIL_H_
	if(!check_io::validate_email(mail))
		std::cout<<"this is no real email address\n";
		// or return with error code example:
		// std::pair<userdata,bool> where
		// userdate is the new data and the bool flag shows if the data is correct
#endif
	cin.ignore(80,'\n');
	cout<<"Age: ";
	cin>>age;
#ifdef _VALIDATE_INTEGER_H_
 	if(check_io::isnum(age))
		std::cerr<<"wrong age input\n";
	// or set the the pair flag wo wrong 
#endif
	cin.ignore(80,'\n');
	return userdata(n,ln,mail,age);
}

const bool operator<(const userdata& one, const userdata& other){
	if(one.last_name_==other.last_name_)
		return one.last_name_<other.last_name_;
	return one.last_name_==other.last_name_;
}
const bool operator==(const userdata &one,const userdata &other){
	if(one.last_name_==other.last_name_)
		return one.name_==other.name_;
	return false;
}

// do the formatting like you want.. it isnt that important ...
std::ostream& operator<<(std::ostream &ostr,const userdata &dat){
	ostr<<"Name		 : "<<dat.name_<<"\n";
	ostr<<"Lastname	 : "<<dat.last_name_<<"\n";
	ostr<<"Email		 : "<<dat.email_<<"\n";
	ostr<<"Age		 : "<<dat.age_<<"\n";
	return ostr;
}
// end of the example


//************************************************
	// database class
//************************************************
template<class data_t>
class database{
typedef typename std::list<data_t> data_list_t;

public:
	explicit database(){}
	const bool add(const data_t &dat);
	const bool del(const data_t &dat);
	void show_all()const;
	const data_list_t& get_list()const{return data_list;}
	const bool input();
	const bool is_in(const data_t &dat);
	const bool  del_all();
private:
	data_list_t data_;
};

template<class data_t>
const bool database<data_t>::add(const data_t& dat){
	if(is_in(dat)){
#ifdef DEBUG
		std::cout<<"\t\t\t data already in\n";
#endif
		return false;
	}
	data_.insert(data_.begin(),dat);
	data_.sort();
	return true;
}

template<class data_t>
const bool database<data_t>::is_in(const data_t & dat){
	return (std::find(data_.begin(),data_.end(),dat))!=data_.end();
}

template<class data_t>
const bool database<data_t>::del(const data_t &dat){
	if(!is_in(dat) && data_.empty()){
#ifdef DEBUG
 	std::cout<<"\t\t\t no such data !!\n";
#endif
		return false;
	}
	data_.erase(std::find(data_.begin(),data_.end(),dat));
	return true;
}

template<class data_t>
void database<data_t>::show_all()const{
	if(data_.empty()){
#ifdef DEBUG
 	std::cout<<"\t\t\tdata_list is empty!!\n";
#endif
		return;
	}
	copy(data_.begin(),data_.end(),std::ostream_iterator<data_t>(std::cout,"\n\n"));
	std::cout<<"\n-------------------------------\n";
	return;
}
template<class data_t>
const bool database<data_t>::del_all(){
	if(data_.empty()){
#ifdef DEBUG
 	std::cout<<"\t\t\tdata_list is empty!!\n";
#endif
		return false;
	}
	data_.clear();
	return true;
}



}// namespace

#endif


----------------------------------------------------------------------
test main

#include "database.hpp"

int main (){
	using namespace database_io;

	try{
	database<userdata> testbase;
	userdata test("foo","bar","foobar@blubb.com",21);
	testbase.add(test);
	testbase.show_all();
	testbase.add(userdata_factory());
	testbase.show_all();
	testbase.del(test);
	testbase.show_all();
	testbase.add(test);
	testbase.show_all();
	if(!testbase.add(test))
		std::cerr<<"data in\n";// will be the case
	if(!testbase.del_all())
		std::cerr<<"del error\n";
	if(!testbase.del_all())
		std::cerr<<"del error\n";// will be the case
	testbase.show_all();



	}catch(...){
		std::cerr<<"exception\n";
		return -1;
	}
	return 0;
}