Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people, just like you, are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions

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, "mysite.com", INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 0);
UseHttpSendReqEx(inetConnect, "c:\\new.txt");
	return 0;

Open in new window

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: www.mysite.com and I don't see any calls to InternetCloseHandle() which is used to end the data transfer.

Open in new window


Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article shows you how to optimize memory allocations in C++ using placement new. Applicable especially to usecases dealing with creation of large number of objects. A brief on problem: Lets take example problem for simplicity: - I have a G…
Go is an acronym of golang, is a programming language developed Google in 2007. Go is a new language that is mostly in the C family, with significant input from Pascal/Modula/Oberon family. Hence Go arisen as low-level language with fast compilation…
Video by: Grant
The goal of this video is to provide viewers with basic examples to understand and use nested-loops in the C programming language.
The viewer will learn how to pass data into a function in C++. This is one step further in using functions. Instead of only printing text onto the console, the function will be able to perform calculations with argumentents given by the user.

789 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question