Opens an existing named event object.

Syntax

HANDLE WINAPI OpenEvent(
  __in  DWORD dwDesiredAccess,
  __in  BOOL bInheritHandle,
  __in  LPCTSTR lpName
);

Parameters

dwDesiredAccess [in]

The access to the event object. The function fails if the security descriptor of the specified object does not permit the requested access for the calling process. For a list of access rights, see Synchronization Object Security and Access Rights.

bInheritHandle [in]

If this value is TRUE, processes created by this process will inherit the handle. Otherwise, the processes do not inherit this handle.

lpName [in]

The name of the event to be opened. Name comparisons are case sensitive.

This function can open objects in a private namespace. For more information, see Object Namespaces.

Terminal Services:  The name can have a "Global\" or "Local\" prefix to explicitly open an object in the global or session name space. The remainder of the name can contain any character except the backslash character (\). For more information, see Kernel Object Namespaces.

Windows XP Home Edition:  Fast user switching is implemented using Terminal Services sessions. The first user to log on uses session 0, the next user to log on uses session 1, and so on. Kernel object names must follow the guidelines outlined for Terminal Services so that applications can support multiple users.

Windows 2000:  If Terminal Services is not running, the "Global\" and "Local\" prefixes are ignored. The remainder of the name can contain any character except the backslash character.

Return Value

If the function succeeds, the return value is a handle to the event object.

If the function fails, the return value is NULL. To get extended error information, call GetLastError.

Remarks

The OpenEvent function enables multiple processes to open handles of the same event object. The function succeeds only if some process has already created the event by using the CreateEvent function. The calling process can use the returned handle in any function that requires a handle to an event object, subject to the limitations of the access specified in the dwDesiredAccess parameter.

The handle can be duplicated by using the DuplicateHandle function. Use the CloseHandle function to close the handle. The system closes the handle automatically when the process terminates. The event object is destroyed when its last handle has been closed.

Requirements

See Also

CloseHandle

CreateEvent

CreateProcess

DuplicateHandle

Event Objects

Object Names

PulseEvent

ResetEvent

SetEvent

Synchronization Functions

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Build date: 11/19/2009