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Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?)

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On 10/15/11 7:32 PM, someone wrote:
> On 16 Okt., 01:12, someone<newsbo...@gmail.com>  wrote:
>> integer value of 72, even though I cannot get it right yet... Guess
>> I'm casting incorrectly from char* to int.
>
> Oooops... Stupid me! I had outcommented the correct file name and used
> a much smaller working file in the line: infile.open("DELETEME.res",
> ios::in|ios::binary)
>
> --- sorry guys, maybe it's too late to work for me now! :-)
>
>
> Last question for today and I shall soon close the thread: Can I ask
> you which of the following you think is the best to use (or suggest
> alternatives)?
>
>
>    if (0) // my way of switching between alternate "solutions" when I
> want both in the code
>       R1_begin = *(reinterpret_cast<unsigned char*>  (&memblock[0]));//,
> 1, 'uint32',endianNess);
>    else
>       memcpy(&R1_begin,&memblock[0], sizeof(R1_begin));
>
>
> ?

The first doesn't do what you want. &memblock[0] is already a char* so 
casting it to unsigned char* and dereferencing isn't going to make a big 
change. If you did a cast to unsigned int*, that would be different.


You also shouldn't use reinterpret_cast here, static_cast is good 
enough, and is actually what you want.

The memcpy is better, as the cast has the danger that some fields might 
not line up on the right word boundaries in your data buffer. It also 
says you can later change them to the network order calls later to make 
your program more portable.

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reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-15 12:00 -0700
  Re: reading binary file into memory. Converting from char to uint32,   float, double, ASCII strings etc (static_cast< > ?) Ian Collins <ian-news@hotmail.com> - 2011-10-16 09:29 +1300
    Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-15 14:17 -0700
      Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Ebenezer <woodbrian77@gmail.com> - 2011-10-15 14:41 -0700
      Re: reading binary file into memory. Converting from char to uint32,   float, double, ASCII strings etc (static_cast< > ?) Ian Collins <ian-news@hotmail.com> - 2011-10-16 10:45 +1300
        Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Martin Jørgensen <mjoerg@gmail.com> - 2011-10-15 15:43 -0700
          Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-15 21:37 -0400
            Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-15 23:23 -0700
              Re: reading binary file into memory. Converting from char to uint32,   float, double, ASCII strings etc (static_cast< > ?) Ian Collins <ian-news@hotmail.com> - 2011-10-16 20:53 +1300
                Re: reading binary file into memory. Converting from char to uint32,   float, double, ASCII strings etc (static_cast< > ?) Paavo Helde <myfirstname@osa.pri.ee> - 2011-10-16 03:04 -0500
                Re: reading binary file into memory. Converting from char to uint32,   float, double, ASCII strings etc (static_cast< > ?) Ian Collins <ian-news@hotmail.com> - 2011-10-16 21:52 +1300
            Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-10-16 18:21 +0000
              Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-16 16:40 -0400
                Re: reading binary file into memory. Converting from char to uint32,   float, double, ASCII strings etc (static_cast< > ?) Ian Collins <ian-news@hotmail.com> - 2011-10-17 10:00 +1300
                Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-16 15:19 -0700
                Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-16 20:03 -0400
                Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-16 17:49 -0700
                Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-16 21:29 -0400
                Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-10-17 09:10 +0000
  Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-15 17:35 -0400
    Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Martin Jørgensen <mjoerg@gmail.com> - 2011-10-15 15:39 -0700
      Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-15 16:12 -0700
        Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-15 16:32 -0700
          Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-15 19:41 -0400
            Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-16 11:33 -0700
              Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Paavo Helde <myfirstname@osa.pri.ee> - 2011-10-16 13:54 -0500
                Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Paavo Helde <myfirstname@osa.pri.ee> - 2011-10-16 14:01 -0500
                Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-16 15:12 -0700
                Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Richard Damon <news.x.richarddamon@xoxy.net> - 2011-10-16 20:14 -0400
                Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-16 17:56 -0700
      Re: reading binary file into memory. Converting from char to uint32,   float, double, ASCII strings etc (static_cast< > ?) Ian Collins <ian-news@hotmail.com> - 2011-10-16 12:33 +1300
        Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-15 16:37 -0700
        Re: reading binary file into memory. Converting from char to uint32,   float, double, ASCII strings etc (static_cast< > ?) Leigh Johnston <leigh@i42.co.uk> - 2011-10-16 19:59 +0100
          Re: reading binary file into memory. Converting from char to uint32,   float, double, ASCII strings etc (static_cast< > ?) Leigh Johnston <leigh@i42.co.uk> - 2011-10-16 20:13 +0100
            Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Joshua Maurice <joshuamaurice@gmail.com> - 2011-10-17 18:17 -0700
              Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Joshua Maurice <joshuamaurice@gmail.com> - 2011-10-17 18:32 -0700
  Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Pavel <pauldontspamtolk@removeyourself.dontspam.yahoo> - 2011-10-15 19:56 -0400
    Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-15 23:27 -0700
      Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Paavo Helde <myfirstname@osa.pri.ee> - 2011-10-16 02:48 -0500
        Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-16 10:57 -0700
          Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Paavo Helde <myfirstname@osa.pri.ee> - 2011-10-16 13:18 -0500
            Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-16 12:52 -0700
  Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-16 10:58 -0700
    Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Paavo Helde <myfirstname@osa.pri.ee> - 2011-10-16 13:37 -0500
      Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) someone <newsboost@gmail.com> - 2011-10-16 14:37 -0700
        Re: reading binary file into memory. Converting from char to uint32, float, double, ASCII strings etc (static_cast< > ?) Paavo Helde <myfirstname@osa.pri.ee> - 2011-10-17 01:21 -0500

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