Reading Bytes in binary file

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January 4th, 2004, 08:36 AM

magicow

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Reading Bytes in binary file

I am doing a project on C++...
I need to dump the content of a binary file to the screen, that is each byte in that file is being print out.

How can I do this?
Please help...

January 4th, 2004, 08:50 AM

mitakeet

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So dump it. I presume what you really mean is that you want to see a text representation of the binary data in the file, right? You can dump it in integer, hex, ones and zeros, even base 64 if you have a mind. You can print the hex representation by taking each character value in the binary file and doing a printf("%x", charVal).

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January 4th, 2004, 09:04 AM

magicow

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What i mean is that...

if I use "od -t x1 test.bin"
the content is :
0000000 45 4c 01 02 73 72

Then the C++ project need to have the following output:
45 4c 01 02 73 72

I am using UNIX

January 4th, 2004, 09:12 AM

mitakeet

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It is printing in hex, us the printf statement I showed you.

January 4th, 2004, 09:14 AM

magicow

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In fact, I want to know how to get those "bytes" out from a binary file?

I have tried to use .get and .read, but failed....

January 4th, 2004, 09:24 AM

mitakeet

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I am most familiar with C I/O, but this will work just as well in C++:

Code:

#include <stdio.h>

int main(){
    FILE *fin;
    int val, cnt=0;

    if ((fin = fopen("somefile.txt", "rb")) == NULL){
        fprintf(stderr, "Can't open file for reading!\n");
        return 1;
    }
    while ((val = fgetc(fin)) != EOF){
        printf("%02X ", (unsigned char) val);
        cnt++;
        if (cnt % 20 == 0)
            printf("\n");
    }
    fclose(fin);
    printf("\n");
    return 0;
}

January 4th, 2004, 09:56 AM

magicow

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Thanks, i get it...

Reading Bytes in binary file

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