Windows IPC

/*
==========================================================================

Purpose:

This is a sample code that demonstrates for the following:

* Working with Named pipe server as a client

Notes:

* 

Author:

* Swarajya Pendharkar

Date:

* 6th April 2006

Updates:

* 
                      
==========================================================================
*/

#include "stdafx.h"
#include "windows.h"

#define g_szPipeName "\\\\.\\Pipe\\MyNamedPipe"  //Name given to the pipe
//Pipe name format - \\servername\pipe\pipename
//This pipe is for server on the same computer, however, pipes can be used to
//connect to a remote server

#define BUFFER_SIZE 1024 //1k
#define ACK_MESG_RECV "Message received successfully"

int main(int argc, char* argv[])
{
     HANDLE hPipe;
     
     //Connect to the server pipe using CreateFile()
     hPipe = CreateFile( 
          g_szPipeName,   // pipe name 
          GENERIC_READ |  // read and write access 
          GENERIC_WRITE, 
          0,              // no sharing 
          NULL,           // default security attributes
          OPEN_EXISTING,  // opens existing pipe 
          0,              // default attributes 
          NULL);          // no template file 
     
     if (INVALID_HANDLE_VALUE == hPipe) 
     {
          printf("\nError occurred while connecting to the server: %d", GetLastError()); 
          //One might want to check whether the server pipe is busy
          //This sample will error out if the server pipe is busy
          //Read on ERROR_PIPE_BUSY and WaitNamedPipe() for that
          return 1;  //Error
     }
     else
     {
          printf("\nCreateFile() was successful.");
     }
     
     //We are done connecting to the server pipe, 
     //we can start communicating with the server using ReadFile()/WriteFile() 
     //on handle - hPipe
     
     char szBuffer[BUFFER_SIZE];
     
     printf("\nEnter a message to be sent to the server: ");
     gets(szBuffer);
     
     DWORD cbBytes;
     
     //Send the message to server
     BOOL bResult = WriteFile( 
          hPipe,                // handle to pipe 
          szBuffer,             // buffer to write from 
          strlen(szBuffer)+1,   // number of bytes to write, include the NULL
          &cbBytes,             // number of bytes written 
          NULL);                // not overlapped I/O 
     
     if ( (!bResult) || (strlen(szBuffer)+1 != cbBytes))
     {
          printf("\nError occurred while writing to the server: %d", GetLastError()); 
          CloseHandle(hPipe);
          return 1;  //Error
     }
     else
     {
          printf("\nWriteFile() was successful.");
     }
     
     //Read server response
     bResult = ReadFile( 
          hPipe,                // handle to pipe 
          szBuffer,             // buffer to receive data 
          sizeof(szBuffer),     // size of buffer 
          &cbBytes,             // number of bytes read 
          NULL);                // not overlapped I/O 
     
     if ( (!bResult) || (0 == cbBytes)) 
     {
          printf("\nError occurred while reading from the server: %d", GetLastError()); 
          CloseHandle(hPipe);
          return 1;  //Error
     }
     else
     {
          printf("\nReadFile() was successful.");
     }
     
     printf("\nServer sent the following message: %s", szBuffer);
     
     CloseHandle(hPipe);
     return 0; //Success
}