From:	buers AT gmx DOT de (Dieter Buerssner)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: binary to float
Date:	23 Feb 2000 14:34:30 GMT
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Neohashi AT mail DOT tele DOT dk (neohashi) wrote in <890hch$49b$1 AT news DOT inet DOT tele DOT dk>:

>Can any one explain to me how do I get 4 bytes(IEEE float) into a 
>floating point var? (it need to be reversed to)

DJGPP uses the IEEE-formats, i.e. type float is 4 byte IEEE float.
The only problem may arise from the endianess of the format.
If you have to swap endianess, the following code snippet may
work. (untested)

  FILE *fp; 
  unsigned char rawdata[4];
  unsigned char t;
  float x;

  fp = fopen("binfloat.dat", "rb");
  if (fp) 
  {
    if (fread(rawdata, sizeof rawdata, 1, fp) == 1)
    {
      /* swap endianess */
      t = rawdata[0]; rawdata[0] = rawdata[3]; rawdata[3] = t;
      t = rawdata[1]; rawdata[1] = rawdata[2]; rawdata[2] = t;
      x = *(float *)rawdata; /* x is the float you wanted */
    }
  }

Dieter

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