From: Chris Holmes <cholmes AT surfsouth DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: From Bytes to Int and Char
Date: Fri, 13 Aug 1999 23:17:37 -0400
Organization: Georgia Institute of Technology, Atlanta GA, USA
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To: djgpp AT delorie DOT com
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Campbell, Rolf [SKY:1U32:EXCH] wrote:
> 
> Nick wrote:
> 
> > I am trying to load some data from a files, the 6 and 7th bytes are an
> > Integer and so are the 11th and 12th.  How do I make them into an INT?  This
> > is what I used earlier
> >
> > char ver, type;
> > int sz, tz;
> >
> > sz = file_buffer[6] + file_buffer[7];
> > is that right?
> 
>     No.  Here's the right way to do it.  This code is not edian safe.
> 
> sz = *(short*)(file_buffer+6);
 
  (sorry... have to say it) They aren't endians, they're native 
arrangements.  Please, be PC with your PC.  <grin>

  One solution (kinda tricky because you need to make sure they are 
stored on a 2 byte boundary or hack around my trick, which is a hack
itself).
  Given: void *buffer;
  make: char *c_buffer=(char *)buffer;
  make: short *i_buffer=(short *)buffer;
  then: short i = i_buffer[BYTE_OFFSET / 2];

  (this should be a little more endian safe)

  Chris