Specif Record Read error in random access files.

Hi i could not specific Record from my binary file. This is the method to list out all records.

Code:

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int student :: showall(fstream &fp)
{
    student rec;
    fp.seekg(0,ios::beg);
    int i=0;
    cout<<"Position\tRoll No\t\tName\tBalance"<<endl;
    while(fp.read((char*)&rec,sizeof rec))
    {   
        cout<<i*sizeof rec<<"\t";
        rec.show();
        i++;
    }
}

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While running this i got the below output

Quote:

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Position Roll No Name Balance
0 1 Heartly 10
28 2 Heartly 20
56 3 Heartly 30
84 4 Heartly 40
112 5 Heartly 50
140 6 Heartly 60
168 7 Heartly 70
196 8 Heartly 80
224 9 Heartly 90
252 10 Heartly 100

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Now i want to search specific record. I gave RecNo 5 to search. This is my View method

Code:

---

int student :: view(fstream &fp,int RecNum)
{
    student rec;
    std::ios::pos_type SearchPosition = RecNum*sizeof rec;
    cout<<endl<<"Position="<<SearchPosition<<endl;
    if( fp.seekg(SearchPosition) == 0 )
    {
        cout<<endl<<"Position="<<SearchPosition<<endl;
            if(fp.read((char*)&rec,sizeof rec))
                    rec.show();
        else
            cout<<endl<<"Read Error .. ! "<<endl;
        }
    else
    {
        cout<<endl<<"Record Number Not Found"<<endl;
    }   
}

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After running this method , i got below result.

Quote:

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Record number (-1 Cancels):
5

Position=140

Record Number Not Found

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Why it is not locating the specific Record?
I also given below my coding of calling the method

Code:

---

    printf("\nMenu : AddDummy, Add, View, Edit, List or Quit ( U, A, V, E, L or Q) : ");
    switch(toupper(getchar()))
    {
    case 'U' :
            file.open("abc.cli",ios::in|ios::out|ios::binary|ios::app);
                cout<<"Creating dummy file of 1000 entries"<<endl;
                record.adddummy(file);
            file.clear();
                break;
        case 'A' :
        file.open("abc.cli",ios::in|ios::out|ios::binary|ios::app);
                  record.get();
        record.add(record,file);
            cout<<"Record Added"<<endl;
        file.clear();
            break;             
        case 'E' :
        file.open("abc.cli",ios::in|ios::out|ios::binary|ios::ate);
                  cout<<endl<<"Record number (-1 Cancels): "<<endl;
                  cin>>Rec;
                  if (Rec > -1)
        {
                    record.get();
            if(!record.update(record,file,Rec))
                cout<<"Record Edited"<<endl;
            else
                    cout<<"Record Edited Failed"<<endl;
            file.clear();
        }                         
        break;
        case 'V' :
        file.open("abc.cli",ios::in|ios::out|ios::binary|ios::ate);
                cout<<endl<<"Record number (-1 Cancels): "<<endl;
                  cin>>Rec;
                  if (Rec > -1)
                    record.view(file,Rec);
        file.clear();
                  break;
        case 'L' :
        file.open("abc.cli",ios::in|ios::out|ios::binary|ios::ate);
                  record.showall(file);
        file.clear();
                  break;
    case 'Q' :
                  file.close();
        return 0;
    default :
            cout<<" \nNot Matching\n ";
    }while(getchar() != '\n');

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Why its not reading the specific Record?