Infinite array size???

This is a discussion on Infinite array size??? within the C++ Programming forums, part of the General Programming Boards category; I have a text file, say it is text.txt, and I want to put it in an array, but I ...

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    Question Infinite array size???

    I have a text file, say it is text.txt, and I want to put it in an array, but I don't want there to be a limit on the array's size. I want it to be able to handle insanely large number of characters in a string, and then overwrite the text with the output.

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    Then you want the STL.

    A vector<string> is effectively a boundless array of boundless arrays of characters.

    If you want them to be indexed by keywords, then a map<string, string> would be more effective.

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    You can use vector or create a class that loops and creates new variables with each input using new keyword. Vectors may be easier though.
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    1) Does a "vector" work like a string (same commands...)

    2) How do I declare a vector/ use it?

    Thanks!

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    No, it works much less like a string and rather more like a vector.

    You can find a bit of info here. (And yes I looked over this one first to make sure the info was at least semi legit)

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    Re: Infinite array size???

    Originally posted by Trauts
    I want it to be able to handle insanely large number of characters in a string, and then overwrite the text with the output.
    Perhaps you should consider to only read portions of the file at one time, process it and then read some more.

    If you really mean insanely large, remember that most implementations of fstream has a 2-4 GB file size limit (actually this has caused me some trouble) and you can never allocate more than 4 GB memory on a windows system (Win32, that is, win64 is not very common).
    Last edited by Sang-drax : Tomorrow at 02:21 AM. Reason: Time travelling

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    an insanely large number of characters... not of file size.

    I'll just do part of a file at a time... no point in learning that before I'm ready
    Last edited by Trauts; 11-03-2002 at 03:45 PM.

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    Carnivore ('-'v) Hunter2's Avatar
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    most implementations of fstream has a 2-4 GB file size limit
    I'm confused... I made a program that created a 27 gb text file... what am I missing?
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    Originally posted by Hunter2
    I'm confused... I made a program that created a 27 gb text file... what am I missing?
    nothing, your implemenation does not have this limit.
    hello, internet!

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    ... okay, sounds good
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    Originally posted by Hunter2
    I'm confused... I made a program that created a 27 gb text file... what am I missing?
    Did you use Windows API functions? The API functions are always capable of creating large files.

    But most (some?) implementations of the standard library uses a 32-bit integer to store the filesize. Naturally, problems occur when opening a file larger than 4GB.
    Last edited by Sang-drax : Tomorrow at 02:21 AM. Reason: Time travelling

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    Well, I used a std:fstream and used a for loop, each iteration writing another character to the file... is that Windows API?
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    no
    Last edited by Sang-drax : Tomorrow at 02:21 AM. Reason: Time travelling

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    What? No analysis of why it worked based on my response?
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    >But most (some?) implementations of the standard library uses a 32-bit integer to store the filesize

    I currently use API specific functions to handle files. However, I am thinking about re-writing large parts of my code to make it non-OS specific & portable. I need to access large files (i.e. size > 4GB).

    Are you saying that standard C++ methods do not allow for files > 4GB on a 32 bit OS?
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