Append Data to Remote File Using Wininet

Posted on 2011-03-19
Last Modified: 2012-05-11
Hello, having some difficulties appending the contents of one file to the contents of another remote file.

// httpPutFile.cpp : Defines the entry point for the console application.
#include "stdafx.h"
#include <windows.h>
#include "wininet.h"
#include <stdio.h>
#pragma comment(lib, "wininet.lib")
int UseHttpSendReqEx(HINTERNET hConnect, char *upFile)
     INTERNET_BUFFERS BufferIn = {0};
     DWORD dwBytesRead;
     DWORD dwBytesWritten;
     BYTE pBuffer[1024]; // Read from file in 1K chunks
     BOOL bRead, bRet;

     BufferIn.dwStructSize = sizeof( INTERNET_BUFFERS );

     HINTERNET hRequest = HttpOpenRequest(hConnect, "PUT", "/logs.bin", NULL, "localhost", NULL, INTERNET_FLAG_HYPERLINK, 0);
     if (!hRequest)
       printf("Failed to open request handle: %lu\n", GetLastError ());
       return FALSE;

     HANDLE hFile = CreateFile (upFile, GENERIC_READ, FILE_SHARE_READ,
     if (hFile == INVALID_HANDLE_VALUE)
       printf("\nFailed to open local file %s.", upFile);
       return FALSE;

     BufferIn.dwBufferTotal = GetFileSize (hFile, NULL);
     printf ("File size is %d\n", BufferIn.dwBufferTotal );

     if(!HttpSendRequestEx( hRequest, &BufferIn, NULL, HSR_INITIATE, 0))
       printf( "Error on HttpSendRequestEx %lu\n",GetLastError() );
       return FALSE;

     DWORD sum = 0;
       if  (!(bRead = ReadFile (hFile, pBuffer, sizeof(pBuffer),
           &dwBytesRead, NULL)))
         printf ("\nReadFile failed on buffer %lu.",GetLastError());
       if (!(bRet=InternetWriteFile( hRequest, pBuffer, dwBytesRead,
         printf ("\nInternetWriteFile failed %lu", GetLastError());
       sum += dwBytesWritten;
     while (dwBytesRead == sizeof(pBuffer)) ;

     CloseHandle (hFile);
     printf ("Actual written bytes: %d\n", sum);

     if(!HttpEndRequest(hRequest, NULL, 0, 0))
       printf( "Error on HttpEndRequest %lu \n", GetLastError());
       return FALSE;
     return TRUE;

int main(int argc, char* argv[])
	HINTERNET inetOpen;
HINTERNET inetConnect;
inetConnect=InternetConnect(inetOpen, "", INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 0);
UseHttpSendReqEx(inetConnect, "c:\\new.txt");
	return 0;

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the output of the application is "File size is 17
Actual written bytes: 17"

I would assume this means it actually was able to write to the remote file, however, the remote file remains unchanged.

Any input;
Question by:JoeD77
1 Comment

Accepted Solution

MedievalWarrior earned 500 total points
ID: 35179674
It's documented that you should resolve the full address as in: and I don't see any calls to InternetCloseHandle() which is used to end the data transfer.

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