From: Martin Ambuhl <mambuhl AT earthlink DOT net>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: fseek()/ fread() troubles
Date: Sun, 02 May 1999 20:33:42 -0400
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To: djgpp AT delorie DOT com
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benvg AT hotpop DOT com wrote:
> 
> I've been trying to use fseek and fread to do some file i/o but weird things
> are happening. I can't seem to figure it out so I wrote this short program,
> and maybe someone can help me out.

Kill the magic numbers and call fseek correctly:

[ ... ]
#if 0
        write(fileno(fp), &data, 20);
#endif
        fwrite(&data, sizeof(STRUCTURE), 1, fp);   /* mha */
        data.number++;
    }
[ ... ]    
#if 0
        fseek_ret = fseek(fp, SEEK_SET, rand_num * 20);
#endif        
        fseek_ret = fseek(fp,rand_num * sizeof(STRUCTURE), SEEK_SET);
        ftell_ret = ftell(fp);

#if 0
        fread(&data, 20, 1, fp);
#endif        
        fread(&data, sizeof(STRUCTURE), 1, fp);
[ ... ]






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-- 
Martin Ambuhl (mambuhl AT earthlink DOT net)
Note: mambuhl AT tiac DOT net will soon be inactive