获得当前进程的下文

//进程描述信息
typedef struct _tagPROCESSINFO
{
DWORD  dwPID;
TCHAR  strPath[_MAX_PATH];
TCHAR  strName[_MAX_FNAME];

} PROCESSINFO, *LPPROCESSINFO;


//获取进程信息列表
BOOL EnumProcessesInfo( PROCESSINFO* lpPsInfo, ULONG ulSize, ULONG* pulNeeded )
// lpPsInfo [out] : 指向PROCESSINFO结构数组的指针
// nSize [in] : lpPsInfo中的元素个数
// nNeeded [out] : 实际的元素个数
// 返回值 : TRUE : 成功; FALSE : 失败
{
ASSERT( pulNeeded );

LPDWORD        lpdwPIDs ;   //存储进程ID数组
DWORD          dwbSize, dwbSize2;

dwbSize2 = 256 * sizeof( DWORD );
lpdwPIDs = NULL;

do {

  if( lpdwPIDs ) {

   HeapFree( GetProcessHeap(), 0, lpdwPIDs );
   dwbSize2 *= 2;
  }

  lpdwPIDs = (LPDWORD)HeapAlloc( GetProcessHeap(), 0, dwbSize2 );
  if( lpdwPIDs == NULL ) {
   return FALSE ;
  }

  if( ! ::EnumProcesses( lpdwPIDs, dwbSize2, &dwbSize ) ) {

   HeapFree( GetProcessHeap(), 0, lpdwPIDs ) ;
   return FALSE ;
  }

}while( dwbSize == dwbSize2 ) ;

ULONG ulCount  = dwbSize / sizeof( DWORD );

//如果为询问数量，则返回实际数量
if ( NULL == lpPsInfo && 0 == ulSize ) {

  *pulNeeded = ulCount;
  return TRUE;
}

ASSERT( lpPsInfo );
if ( NULL == lpPsInfo ) {
  return FALSE;
}

if ( ulSize <= ulCount ) {
  *pulNeeded = ulSize;
}
else {
  *pulNeeded = ulCount;
}

//获得进程信息
HANDLE hProcess;
HMODULE hModule;
DWORD  dwSize;

   
   char path_buffer[_MAX_PATH];
   char drive[_MAX_DRIVE];
   char dir[_MAX_DIR];
   char fname[_MAX_FNAME];
   char ext[_MAX_EXT];
   
// Loop through each ProcID.
for( ULONG ulIndex = 0 ; ulIndex < (*pulNeeded) ; ulIndex++ )
{
  // Open the process (if we can... security does not
  // permit every process in the system).
//  TRACE("PID To Open:%d\r\n", lpdwPIDs[ulIndex] );

  lpPsInfo[ulIndex].dwPID = lpdwPIDs[ulIndex];
      lpPsInfo[ulIndex].strPath[0] = 0;
      lpPsInfo[ulIndex].strName[0] = 0;
      
      // Because Can't Open 0 And 8 Process,
      // Mark Them At There
      if ( 0 == lpdwPIDs[ulIndex] ) {

         strcpy( lpPsInfo[ulIndex].strName, "System Idle Process" );
         continue;
      }
      else if ( 8 == lpdwPIDs[ulIndex] ) {

         strcpy( lpPsInfo[ulIndex].strName, "System" );
         continue;
      }

      // Open Process And Get Process Infomation
  hProcess = OpenProcess(
       PROCESS_QUERY_INFORMATION | PROCESS_VM_READ,
       FALSE, lpPsInfo[ulIndex].dwPID );
  if( hProcess != NULL )
  {
   // Here we call EnumProcessModules to get only the
   // first module in the process this is important,
   // because this will be the .EXE module for which we
   // will retrieve the full path name in a second.
   if( EnumProcessModules( hProcess, &hModule,
      sizeof(hModule), &dwSize ) ) {

    // Get Full pathname:
    if( GetModuleFileNameEx( hProcess, hModule,
                     path_buffer, sizeof(path_buffer) ) ) {
               
               _tsplitpath( path_buffer, drive, dir, fname, ext );               
               strcpy( lpPsInfo[ulIndex].strPath, path_buffer );
               sprintf( lpPsInfo[ulIndex].strName, "%s%s", fname, ext );
//               TRACE( "ModuleFileName:%s\r\n", path_buffer );
    }
   }
   CloseHandle( hProcess ) ;
  }
}

return TRUE;
}