Hello all, I have a file which contains the following: 26 25 2F 2D ... That is, all HEX data - interpreted by us as --> & % / - I need to write a C++ code, which will open the file in read mode, and take the input as HEX itself, and not string. That is, the C++ program will interpret the data as HEX digits. I tried, but the program is reading as string. Any help will be welcome.

If you have that hex as characters in the file then your program is indeed correct in reading it out as a string. Those characters, although can be read has hex, are in fact representing completely different data.

open the file in binary mode is the answer I think you are looking for.

Quote:Original post by ambarish_mitra
Hello all,

I have a file which contains the following:
26 25 2F 2D ...


That is, all HEX data - interpreted by us as --> & % / -

I need to write a C++ code, which will open the file in read mode, and take the input as HEX itself, and not string.

That is, the C++ program will interpret the data as HEX digits.

I tried, but the program is reading as string.

Any help will be welcome.

I think you are confused about how data works.

The file contains bytes. Each byte is (and I am making a huge simplification here) a number from 0 to 255, inclusive. We can display this number in many ways. One is to draw a symbol, chosen from a set of 256 symbols, that corresponds to that number. That is, we look it up in the ASCII table, and turn the number 38 into &, 37 into %, 47 into / and 45 into -. Another is to use the symbols 0 through 9 and A through F, and use two such symbols to express the number in human-readable, hexadecimal format. But each of those symbols, in turn, corresponds to a byte.

What is actually in the file? There is no such thing as "HEX data". There can be a file 4 bytes long, which you are viewing with a hex editor (causing it to show "26 25 2F 2D" on screen), or a file with the 4 bytes, which you view with a text editor (such as notepad, causing it to show "&%/-"; or a file with 11 bytes, which you view with a text editor and see "26 25 2F 2D" (i.e. a hex representation of some data), or a file with 11 bytes, which you view with a hex editor and see ... well, see if you can figure that out for yourself. :) (The space character has numeric value 32; digits are 48 through 57; capital letters are 65 through 90.)

Now, given what's in the file, what do you want to end up in memory?