Re: BYTE?

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From: Carl Daniel [VC++ MVP] (cpdaniel_remove_this_and_nospam_at_mvps.org.nospam)
Date: 03/25/04 

Date: Thu, 25 Mar 2004 07:08:01 -0800

newbie wrote:
> I am downloading get request for files. The files are basically the
> header followed by bytes of data. What is the best way to process the
> file, removing the header?
> I was going to use the stl string class. But this gave me trouble.
> The problem is I could remove the header but the left over data in
> the buffer got currupted when i cast it from string to BSTR.

I don't see any use of BSTR in the code you show here. You certainly can't
cast anything from "char *" to "BSTR" since the former is a "narrow" string
(8-but characters) and the latter is a "wide" string (16-bit characters).

> Should I
> use string classes, like stl string. Any help greatly appreciated.
> Code even more.
>
> I was trying to do something like this

//onread of socket
void onread(char *data)
{
    //when it is true no longer need to look for header
    if(decodeheader == false)
    {
          buff += data;
          int x = buff.find("\r\n\r\n");
          if(x < string::npos)
          {
               int len = buff.length();
/*
               char *ptr = new char[len];
               buff.copy(ptr,len - x,x);
               WriteFile(hfile,(BYTE *) ptr, len - x, &dwBytesWritten,
NULL);
*/
                // you don't need to allocate a new buffer
                // you do need to account for the \r\n\r\n
                // (unless you want those written to the file)
                x += 4;
                WriteFile(hfile,(BYTE*) buff.c_str()+x, len-x,
&dwBytesWritten, NULL);

              decodeheader = true;
              return true;
          }
    }
    else
    {
        WriteFile(hfile,(BYTE*)data, a, &dwBytesWritten, NULL);
    }
}

While I did make a couple of changes, I don't see anything in your original
code that would lead to "corruption". You did have a memory leak, but then
it's also clear that you've left oiut some of the code. If you could show a
more complete example of what you're trying to do, and describe "corrupted"
a bit better, it would improve the odds of someone posting a solution to
your dilema.

-cd

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