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From: Ian Collins <ian-news@hotmail.com>
Newsgroups: comp.lang.c++
Subject: Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?)
Date: Sun, 16 Oct 2011 10:45:49 +1300
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On 10/16/11 10:17 AM, someone wrote:
> On 15 Okt., 22:29, Ian Collins<ian-n...@hotmail.com>  wrote:
>> On 10/16/11 08:00 AM, someone wrote:
>
>>>     int R1_begin;
>>>     R1_begin = static_cast<typeof R1_begin>    (memblock[0]);//, 1,
>>> 'uint32',endianNess);
>>
>> You can't just cast an array of char to an int and expect the right
>> result (unless the data is written in the same byte order as your machine).
>
> So how should I do it?
> [to begin with, we can just assume that the data is written in the
> same byte order and see if that works...]
>
>> The most convenient way to convert the byte order is to use the network
>> ordering functions (if your platform has them).  See ntohl.
>
> Sorry, I have absolutely no idea about any network functions...
> I was (pretty) sure that somebody had some code they could show here?
> This "ntohl" looks a bit confusing to me - besides that, it's not
> standard C++.

They are typically macros, just look them up if you want to see how they 
work.

>>> And what about big endian / little endian? I'm confused. Looking
>>> forward to hear from you!
>>
>> Google "endian"
>
> I did it. But what I meant is, what are your thoughts about it, when
> reading a binary file like shown in my code?

I use the network byte order functions, that's what they are there for.

-- 
Ian Collins