Thread: gcount() always returning 0

  1. #1
    Registered User
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    gcount() always returning 0

    Whether it's a text file or a binary file gcount() always returning 0 but int size gets the values read.
    Why?

    Code:
       
        int size;
        string str;
        ifstream ifs;
        ifs.open(file, ifstream::binary);
     
        while(!ifs.eof())
        {
            getline(ifs, str);
            cout << ifs.gcount() << " characters read: "  << '\n';
            size = str.size();
            cout << "size " << size << endl;
         }
    Windows 10 with Visual Studio 14.0.

  2. #2
    and the Hat of Guessing tabstop's Avatar
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    I don't think that version of getline changes gcount (just the one that reads into a char* instead).

  3. #3
    Hurry Slowly vart's Avatar
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    Rishon LeZion, Israel
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    FAQ > Why it's bad to use feof() to control a loop - Cprogramming.com

    It explains for C - but same idea applicable to C++ - so you could benefit from reading this FAQ
    All problems in computer science can be solved by another level of indirection,
    except for the problem of too many layers of indirection.
    David J. Wheeler

  4. #4
    Registered User
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    Thank you, that was useful.
    Last edited by Ducky; 10-20-2013 at 03:43 AM.
    Windows 10 with Visual Studio 14.0.

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