显示“关闭”对话框
以下示例使用 InitiateSystemShutdown 函数重新启动本地系统。 系统显示一个对话框,其中包含一条自定义消息,并向用户显示一条消息,以在指定的超时间隔 (30 秒) 关闭应用程序。 超时间隔过后,系统将重启。
在调用 InitiateSystemShutdown 之前,应用程序必须启用SE_SHUTDOWN_NAME特权。 有关详细信息,请参阅 特权。
#include <windows.h>
#pragma comment( lib, "advapi32.lib" )
BOOL MySystemShutdown( LPTSTR lpMsg )
{
HANDLE hToken; // handle to process token
TOKEN_PRIVILEGES tkp; // pointer to token structure
BOOL fResult; // system shutdown flag
// Get the current process token handle so we can get shutdown
// privilege.
if (!OpenProcessToken(GetCurrentProcess(),
TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken))
return FALSE;
// Get the LUID for shutdown privilege.
LookupPrivilegeValue(NULL, SE_SHUTDOWN_NAME,
&tkp.Privileges[0].Luid);
tkp.PrivilegeCount = 1; // one privilege to set
tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
// Get shutdown privilege for this process.
AdjustTokenPrivileges(hToken, FALSE, &tkp, 0,
(PTOKEN_PRIVILEGES) NULL, 0);
// Cannot test the return value of AdjustTokenPrivileges.
if (GetLastError() != ERROR_SUCCESS)
return FALSE;
// Display the shutdown dialog box and start the countdown.
fResult = InitiateSystemShutdown(
NULL, // shut down local computer
lpMsg, // message for user
30, // time-out period, in seconds
FALSE, // ask user to close apps
TRUE); // reboot after shutdown
if (!fResult)
return FALSE;
// Disable shutdown privilege.
tkp.Privileges[0].Attributes = 0;
AdjustTokenPrivileges(hToken, FALSE, &tkp, 0,
(PTOKEN_PRIVILEGES) NULL, 0);
return TRUE;
}
如果在 InitiateSystemShutdown 指定的超时期限内执行 AbortSystemShutdown 函数,则系统不会关闭。 例如,如果在 MySystemShutdown 之后调用 PreventSystemShutdown,则系统会关闭对话框,并且不会重启系统。
#include <windows.h>
#pragma comment( lib, "advapi32.lib" )
BOOL PreventSystemShutdown()
{
HANDLE hToken; // handle to process token
TOKEN_PRIVILEGES tkp; // pointer to token structure
// Get the current process token handle so we can get shutdown
// privilege.
if (!OpenProcessToken(GetCurrentProcess(),
TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken))
return FALSE;
// Get the LUID for shutdown privilege.
LookupPrivilegeValue(NULL, SE_SHUTDOWN_NAME,
&tkp.Privileges[0].Luid);
tkp.PrivilegeCount = 1; // one privilege to set
tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
// Get shutdown privilege for this process.
AdjustTokenPrivileges(hToken, FALSE, &tkp, 0,
(PTOKEN_PRIVILEGES)NULL, 0);
if (GetLastError() != ERROR_SUCCESS)
return FALSE;
// Prevent the system from shutting down.
if ( !AbortSystemShutdown(NULL) )
return FALSE;
// Disable shutdown privilege.
tkp.Privileges[0].Attributes = 0;
AdjustTokenPrivileges(hToken, FALSE, &tkp, 0,
(PTOKEN_PRIVILEGES) NULL, 0);
return TRUE;
}