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View string from a certain offset in a file

Oct 29, 2015 at 11:47am
Hcode91 (13)
Hello everyone, I been practicing with the filestreams in c++ and I can successfully get the string within a binary file to show on screen. However, the issue I am having is that I only want it to show strings from a certain offset to an end offset.

This is the code I have to display all the strings:

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#include <iostream>
#include <fstream>
#include <cstring>


int main()
{
    std::fstream file("README.bin",std::ios::binary | std::ios::in);

    file.seekg(0);
    char ch;
    while (file.good()){

        file.get(ch);
        std::cout << ch;
    }

    return 0;
}
Edit & run on cpp.sh


The file itself is just a test .bin file. It displays all characters but I only want it to display for example 'test file' and not 'test file @#zxds#' etc.

I'm guessing my issue lies within the seekg method but can't figure it out.

I appreciate any help :)
Oct 29, 2015 at 2:59pm
MiiNiPaa (8886)
Replace 0 in seekg with offset you need.

For example file, seekg(100) will allow you to read info starting from 101th byte
Oct 29, 2015 at 3:20pm
Hcode91 (13)
Thank you :)

The only other thing I'm trying to figure out is how to set an end offset so it doesn't continue to the end of the file?
Oct 29, 2015 at 3:23pm
MiiNiPaa (8886)
Read only needed amound of bytes. end offset - start offset = amount of bytes to read.
Oct 29, 2015 at 3:31pm
Hcode91 (13)
Thank you once again :)

Marking as solved.
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