Streams help

This is a discussion on Streams help within the C++ Programming forums, part of the General Programming Boards category; Been a long time since I coded but i started school today and here is my problem. Basically theres some ...

  1. #1
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    Streams help

    Been a long time since I coded but i started school today and here is my problem. Basically theres some file which called words.txt that you have to read from. You must count the number of words and then display the actual file. This is my code.

    Code:
    #include <iostream>
    #include <fstream>
    #include <string>
    
    using namespace std;
    
    int CountTxt(ifstream&);
    void DispTxt(ifstream&);
    
    int main()
    {
        
        ifstream infile;
        infile.open("words.txt");
        
        if (!infile){
            cerr << "Error reading words.txt \n";
            exit(1);
            system("pause");
        }    
        
        cout<< "There total number of words are: " 
            << CountTxt(infile) << endl;
        
        
        infile.seekg(0);
        cout << "The text from the file was: \n\n";
        DispTxt(infile);
        
        infile.close();
        system("pause");
        return 0;
    }    
    
    int CountTxt(ifstream& in){
        string s;
       unsigned int count(0);
        
        while (in >> s){
            count++;
        }        
        return count; 
    }
    
    void DispTxt(ifstream& in){
        char c;
        in >> noskipws;
        
        while (in >> c){
          cout << c;     
        }   
        
        in >> skipws;
    }
    The problem is this: It reads the # of words fine. But it seems like it gets stuck w/ reading the file b/c afta that it doesnt display the file. But i kno my function for displayin the file works b/c i tried commenting out the first function and it displays the file the right away. Im guessing its having some difficulty with returning to the starting position... any help is appreciated.
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  2. #2
    vae victus! skorman00's Avatar
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    try seekp(), not seekg()

  3. #3
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    isnt seekp used with ostream. then that wouldnt work. and our instructor told us we would have to use seekg in that spot of our code.
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  4. #4
    Cat Lover
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    seekg should work fine.

    "There total number of words are: "
    Should be "The total number of words is: "

  5. #5
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    i know it should work fine but it isnt. thats how we were told to use it and somethin in my code isnt right... help ???
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  6. #6
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    Well, seekg doesn't working properly. Try using
    Code:
    seekg(ios::end);
    seekg(ios::beg);
    Maybe telling it to seek to 0 when it's at wherever it is is screwing it up.

    Is the code after seekg running at all, or is it crashing or similar before?

  7. #7
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    I dont know exactly what the problem is. I'm assuming it has something to do with going through the file a second time because both functions work properly. If you test out the second fucntion alone without running the count, it displays the file with no problems. But running the code i have there my output is this.

    Code:
    The total number of words is: 17
    The text from the file was:
    It never displays the actual text from the file. It only displays it when i dont run the count function. Ive tried seekg() everyway and nothings working.
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  8. #8
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    Well, I'm not at home right now so can't test it unfortunately.

    Well, could always just close then open the file again.

    Have you tried not running the count program, but still using seekg(0)? Does it still work then?

  9. #9
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    yea it works w/ out using the count.

    weve been told not to open and close b/c seekg would eliminate those steps.
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  10. #10
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    I switched the order of the functions to display than count. It displays but then the count is always 0.. it seems like wateva function goes first is working correctly.
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  11. #11
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    You need to clear the fail bits from the stream. The first function reads until the end of file is reached and sets an error flag. Since you are using the same stream, you must call clear() to effectively continue reading from it.

  12. #12
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    Thank you. Thats exactly what i was looking for
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