seekg() problem

This is a discussion on seekg() problem within the C++ Programming forums, part of the General Programming Boards category; Hi, people. I need to write data in file, but not from the file begining. After operating with seekg() to ...

  1. #1
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    seekg() problem

    Hi, people.

    I need to write data in file, but not from the file begining.
    After operating with seekg() to move file pointer, the compiler brings such message: "....'struct std:fstream' has no member named 'seekg' "


    *code*

    ofstream write;

    write.seekg(offset*6, ios::beg);

    ********

    What i did wrong?

  2. #2
    Guest Sebastiani's Avatar
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    XXXg functions are for streams that can 'get' values, and XXXp functions for those that can 'put' values. In other words, istream's fall in the first category, ostreams in the second, and iostreams in both.

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    Guest Sebastiani's Avatar
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    And just to clarify a bit, the reason for all this is that some streams (such as iostreams) support independent read/write 'file' pointers. It probably would have been more logical to simply provide a 'seek' wrapper function for istream/ostream, of course, but that's just the way they decided to do things.

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    If counting my bad english, i understand first reply . Frankly speaking i expect to see a few lines of correct code. )))

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    Quote Originally Posted by Rustik_ View Post
    If counting my bad english, i understand first reply . Frankly speaking i expect to see a few lines of correct code. )))
    Oh, you expect to see a few lines of correct code, just to, you know, speed things up for you?

    You know what we expect ? We expect people to be self-sufficient and capable of doing research on their own. If you had looked up the ofstream class and its method on a site such as C++ Reference, you'd have found that there is no member function called seekg(). Oh wait, the error tells you that already.

    What could possibly tell you why there isn't one? Hmm. That's a tough one.

    Please, don't come on these boards asking a question that reeks of a general lack of self-sufficiency, then demand something more when you do get help.
    "What's up, Doc?"
    "'Up' is a relative concept. It has no intrinsic value."

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    2IceDane:

    hope u know place to put in all your self-sufficiencies

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    Quote Originally Posted by Rustik_ View Post
    2IceDane:

    hope u know place to put in all your self-sufficiencies
    No need to be crass about it - IceDane's comment was to-the-point and perfectly reasonable. If you can't respond in a civil manner then I'd recommend seeking help elsewhere.

    It isn't always easy to take criticism from others, but if you can learn to deal with it I think you'll find that an honest assessment, however critical it may be, is more often than not a valuable thing.

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