createmutex_createevent_releasemutex

MUTEX的释放问题,急

我的程序建立MUTEX,但是程序关闭后并不能释放MUTEX,RELEASEMUTEX总是返回288号错误.这是为什么呀~~~ 急等.

------模块代码

Public Mutex As Long

Public Declare Function CreateMutex Lib "kernel32 " Alias "CreateMutexA " (lpMutexAttributes As SECURITY_ATTRIBUTES, ByVal bInitialOwner As Long, ByVal lpName As String) As Long

Public Declare Function OpenMutex Lib "kernel32 " Alias "OpenMutexA " (ByVal dwDesiredAccess As Long, ByVal bInheritHandle As Long, ByVal lpName As String) As Long

Public Declare Function ReleaseMutex Lib "kernel32 " (ByVal hMutex As Long) As Long

Public Declare Function CloseHandle Lib "kernel32 " (ByVal hObject As Long) As Long

Public Type SECURITY_ATTRIBUTES

nLength As Long

lpSecurityDescriptor As Long

bInheritHandle As Long

End Type

------窗体代码

Private Sub Command1_Click()

Dim sa As SECURITY_ATTRIBUTES

Mutex = CreateMutex(sa, False, "TREXRIII ")

If Err.LastDllError = 183 Then

Label1.Caption = "已存在 " & Mutex

Else

Label1.Caption = "已建立 " & Mutex

End If

End Sub

Private Sub Command2_Click()

ReleaseMutex Mutex

If Err.LastDllError <> 0 Then

Label1.Caption = "释放失败 " & Err.LastDllError

End If

End Sub

回答2：

ReleaseMutex是释放Mutex的所有权。

CreateMutex第二个参数指定当前线程是否拥有Mutex的所有权，若此命名Mutex是你创建的，bInitialOwner又为非零，则当前线程拥有

Mutex的所有权，否则都不会拥有Mutex的所有权！

所以你对bInitialOwner为0时CreateMutex创建的Mutex，调用ReleaseMutex是错误的，错误288代表你无权这样做！

这里，简单CloseHandle关闭即可，在bInitialOwner为非零时调用CreateMutex，你才需调用ReleaseMutex，当然，其后仍需调用

CloseHandle。releasemutex

若你的程序不调用CloseHandle，该Mutex会一直存在，直到程序退出，IDE环境下可能要退出VB才行。releasemutex2014-05-30weitz88

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