windows关机API

NT系统的关机API函数实现过程

前计算机系统多为Windows 2000和Windows XP。Windows 98系统下的关机比较容易，只需要直接调用关闭计算机函数ExitWindowEx就可以了，而在Windows 2000系统下的调用这个函数只能“注销”而不能实现系统关机。在Windows 2000系统实现关机操作得到SHUTDOWN许可，得到SHUTDOWN许可需要调用相应的API函数，具体过程如下： （1）首先得到当前程序的进程句柄； （2）使用这个进程句柄得到当前程序的访问标记； （3）生成TOKEN_PRIVILEGES结构； （4）有了TOKEN_PRIVILEGES结构后再获得SHUTDOWN权限； （5）最后使用ExitWindowEx函数进行相关操作。 1) 相关的API函数     获得当前进程伪句柄函数GetCurrentProcess,函数声明如下：     Private Declare Function GetCurrentProcess Lib "kernel32" () As Long     取得程序访问标记函数OpenProcessToken，函数声明如下：     Private Declare Function OpenProcessToken Lib "advapi32" (ByVal ProcessHandle As Long, ByVal DesiredAccess As Long, TokenHandle As Long) As Long    查找进程权限函数LookupPrivilegeValue，函数声明如下：    Private Declare Function LookupPrivilegeValue Lib "advapi32" Alias "LookupPrivilegeValueA" (ByVal lpSystemName As String, ByVal lpName As String, lpLuid As LUID) As Long    获得关机权限函数AdjustTokenPrivileges，函数声明如下：    Private Declare Function AdjustTokenPrivileges Lib "advapi32" (ByVal TokenHandle As Long, ByVal DisableAllPrivileges As Long, NewState As TOKEN_PRIVILEGES, ByVal BufferLength As Long, PreviousState As TOKEN_PRIVILEGES, ReturnLength As Long) As Long    关机函数ExitWindowEx    Private Declare Function ExitWindowsEx Lib "user32" Alias "ExitWindowsEx" (ByVal uFlags As Long, ByVal dwReserved As Long) As Long      用于关机操作的一些常数如表2所示 常数值 字符标识 作用 &H20 TOKEN_ADJUST_PRIVILEGES 关机权限标识 &H8 TOKEN_QUERY 标识查询 &H2 SE_PRIVILEGE_ENABLED 私有进程有效 0 EWX_LOGOFF 终止进程系统注销 1 EWS_SHUTDOWN 关闭系统电源 2 EWS_REBOOT 重新启动 4 EWS_FORCE 强行终止没有响应的进程

 [C/C++]代码

01 //关闭计算机
02 BOOL MySystemShutdown()
03 {
04    HANDLE hToken;
05    TOKEN_PRIVILEGES tkp;
06
07    // Get a token for this process.
08
09    if (!OpenProcessToken(GetCurrentProcess(),
10         TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken))
11       return( FALSE );
12
13    // Get the LUID for the shutdown privilege.
14
15    LookupPrivilegeValue(NULL, SE_SHUTDOWN_NAME,
16         &tkp.Privileges[0].Luid);
17
18    tkp.PrivilegeCount = 1;  // one privilege to set
19    tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
20
21    // Get the shutdown privilege for this process.
22
23    AdjustTokenPrivileges(hToken, FALSE, &tkp, 0,
24         (PTOKEN_PRIVILEGES)NULL, 0);
25
26    if (GetLastError() != ERROR_SUCCESS)
27       return FALSE;
28
29    // Shut down the system and force all applications to close.
30
31    if (!ExitWindowsEx(EWX_SHUTDOWN | EWX_FORCE,
32                SHTDN_REASON_MAJOR_OPERATINGSYSTEM |
33                SHTDN_REASON_MINOR_UPGRADE |
34                SHTDN_REASON_FLAG_PLANNED))
35       return FALSE;
36
37    return TRUE;
38 }