Source code for parent.cpp

    1: #define WIN32_LEAN_AND_MEAN
    2: #include <windows.h>
    3: #include <stdio.h>
    4: #include <stdlib.h>
    5: #include "sharedmem.h"
    6: 
    7: #define MEM_NAME        "ParentChildSharedMemory"
    8: 
    9: typedef struct _DATA  {
   10:     int  value;
   11:     char sText[ 50 ];
   12: } DATA, *PDATA;
   13: 
   14: HANDLE Run( char* psProgram );
   15: 
   16: 
   17: void main( void )
   18: {
   19:     SharedMem sm;
   20: 
   21:     if ( !sm.Create( sizeof( DATA ), MEM_NAME ) )  {
   22:         printf( "Unable to create shared memory buffer! Error#: %d\n",
   23:                 sm.ErrorNumber() );
   24:         exit( EXIT_FAILURE );
   25:     }
   26: 
   27:     PDATA pdata = (PDATA) sm.GetMem();
   28: 
   29:     // note that we'll need to be in the same directory...
   30:     HANDLE hChild = Run( "child.exe" );
   31: 
   32:     if ( NULL != hChild )  {
   33:         // wait for the child process to finish
   34:         WaitForSingleObject( hChild, INFINITE );
   35: 
   36:         // clean up resources
   37:         CloseHandle( hChild );
   38: 
   39:         // print out what was found in the buffer
   40:         printf( "Parent found the following in shared memory:\n"
   41:                 "Value: %d\nText:  %s\n", pdata->value, 
   42:                 pdata->sText );
   43:     }
   44:     else
   45:         printf( "Unable to run child: %d\n", GetLastError() );
   46: }
   47: 
   48: HANDLE Run( char* psProgram )
   49: {
   50:     STARTUPINFO         si;
   51:     PROCESS_INFORMATION pi;
   52:     BOOL                bStarted;
   53: 
   54:     GetStartupInfo( &si );
   55: 
   56:     // create the consumer
   57:     bStarted = CreateProcess( psProgram, 
   58:                               NULL, NULL, NULL, FALSE,
   59:                               NORMAL_PRIORITY_CLASS, NULL, NULL,
   60:                               &si, &pi );
   61: 
   62:     if ( bStarted )
   63:         return pi.hProcess;
   64:     else
   65:         return NULL;
   66: }
   67: