MdePkg/Include/Library/UefiRuntimeServicesTableLib.h

   1 /** @file
   2   Provides a service to retrieve a pointer to the EFI Runtime Services Table.
   3
   4   This library does not contain any functions or macros.  It simply exports the
   5   global variable gRT that is a pointer to the EFI Runtime Services Table as defined
   6   in the UEFI Specification.  The global variable gRT must be preinitialized to NULL.
   7   The library constructor must set gRT to point at the EFI Runtime Services Table so
   8   it is available at the module's entry point. Since there is overhead in initializing
   9   this global variable, only those modules that actually require access to the EFI
  10   Runtime Services Table should use this library.
  11   Only available to DXE and UEFI module types.
  12
  13 Copyright (c) 2006 - 2008, Intel Corporation<BR>
  14 All rights reserved. This program and the accompanying materials
  15 are licensed and made available under the terms and conditions of the BSD License
  16 which accompanies this distribution.  The full text of the license may be found at
  17 http://opensource.org/licenses/bsd-license.php
  18
  19 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  20 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  21
  22 **/
  23
  24 #ifndef __UEFI_RUNTIME_SERVICES_TABLE_LIB_H__
  25 #define __UEFI_RUNTIME_SERVICES_TABLE_LIB_H__
  26
  27 ///
  28 /// Cached copy of the EFI Runtime Services Table
  29 ///
  30 extern EFI_RUNTIME_SERVICES  *gRT;
  31
  32 #endif