How to determine the size of a file retrieved by http protocol

[gecool]

Hy everyone. My purpose is to download a range of bytes (i.e. from the beggining up to a certain point) from a file located by a given URL. I am trying to determine the remote file size, but so far I didn't succeded. I am using WinInet, InternetReadFile function to actually read the file. I can read it, but I would like to determine it's size prior of downloading the whole file. If anyone could show me another way tp do that, more simple than this please do so. THANKS.:)

[Hans Ruck]

Try:

HttpQueryInfo(hResource, HTTP_QUERY_CONTENT_LENGTH | HTTP_QUERY_FLAG_NUMBER,
&dwContentLength, &dwSize, NULL)

where hResource is the one you use when calling InternetReadFile, dwContentLength is a DWORD to return the file-size into and dwSize = sizeof(DWORD).

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"though nothing  will keep us together  we can beat them  for ever and ever" rechi

[gecool]

Thanx Rechi ;-) One extra question ? R U from Romania ? I tried that, but unfortunately i get: ERROR_HTTP_HEADER_NOT_FOUND ... At first i had this in mind that is to play with such functions like Internetqueryoption and stuff, but no matter how much I dig up those flags I didn't find anyone related to the whole file size, just related to sections ... THANKZ anyway :->

[Hans Ruck]

gecool wrote: ERROR_HTTP_HEADER_NOT_FOUND It's about the headers, take a look at this (old) fragment:

  HINTERNET hResource=::HttpOpenRequest(hConnection, \_T("GET"),
    szRelativeFile, NULL, NULL, NULL,
    INTERNET\_FLAG\_KEEP\_CONNECTION, 0);
  
  if (hResource)
  {
    LPTSTR szHeaders=\_T("Accept: audio/x-aiff, application/octet-stream, "
      "application/x-msdownload, audio/basic, "
      "audio/midi, audio/mpeg, audio/wav, image/jpeg, image/gif, "
      "image/jpg, image/png, image/mng, image/bmp, text/plain, "
      "text/html, text/htm\\r\\n");
    CString szAgentHeader;
    szAgentHeader.Format(\_T("User-Agent: %s/1.0\\r\\n"),
      (LPCTSTR)m\_szAppName);
    HttpAddRequestHeaders(hResource, szHeaders, \_tcslen(szHeaders),
      HTTP\_ADDREQ\_FLAG\_ADD\_IF\_NEW);
    HttpAddRequestHeaders(hResource, (LPCTSTR)szAgentHeader,
      szAgentHeader.GetLength(), HTTP\_ADDREQ\_FLAG\_ADD\_IF\_NEW);
    if (HttpSendRequest(hResource, NULL, 0, NULL, 0))
    {
      DWORD dw=0, dwOut=0, i=0, n=0, dwContentLength,
        dwSize=sizeof(DWORD);
      CString szFileFromPath=CUpgrader::GetFileFromPath(
        szRelativeFile), filepath;

      if (!::HttpQueryInfo(hResource, HTTP\_QUERY\_CONTENT\_LENGTH |
        HTTP\_QUERY\_FLAG\_NUMBER, &dwContentLength, &dwSize, NULL))
          dwContentLength=-1; // unknown

and check if something is missing in your code. It's from an update system i wrote a year ago, and it works like a dream :-> gecool wrote: R U from Romania ? Yeah! :-D

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"though nothing  will keep us together  we can beat them  for ever and ever" rechi

[gecool]

Mersi mult ;-) ;-) ;-) Tocmai asta asteptam sa gasesc un piece of code .... ;-) ;-);-) Geo.