Question

What is wrong with the code below.It runs Perfectly fine for some inputs and crashes for some special inputs?

#include<iostream>
#include<string>
#include<fstream>

using namespace std;


struct event { 

string date,time,content;
bool is_high_priority;

};


int main() {

event one,two;
one.is_high_priority=false;
char tmp;

ofstream out_file("events" , ios::binary );


    cout<<"\nEnter Date(dd.mm) ";
    cin>>one.date;
    cout<<"\nEnter Time(hh:mm:ss) ";
    cin>>one.time;
    cout<<"\nenter content";
    cin>>one.content;

    if(tmp == 't') 
        one.is_high_priority = true;
    else
        one.is_high_priority = false;


    out_file.write((char*) &one, sizeof(one) );

    out_file.close();


    ifstream in_file("events" , ios::binary );
    in_file.read((char*)&two,sizeof(two));

    cout<<two.date<<" "<<two.time<<" "<<two.content<<" "<<two.is_high_priority;

    in_file.close();

}

It crashed for these inputs :
Enter Date(dd.mm) ankmjjdn md

Enter Time(hh:mm:ss)
enter contentsnjs sjnsn

Answer 1

You can’t just save the bytes of a std::string object to a file and later load them again. The std::string contains pointers to dynamically allocated memory, and your save/load will just duplicate the pointer itself, not the pointed to data.