Subclassing and Hooking with Visual Basic

Name

BroadcastSystemMessage

Synopsis

Sends a message to multiple recipients. The recipients are specified in the pdw parameter of this function:

Public Declare Function BroadcastSystemMessage Lib "user32" _
     Alias "BroadcastSystemMessage" _
	(ByVal dw As Long, pdw As Long, ByVal un As Long, ByVal wParam As Long, _
	ByVal lParam As Long) As Long

Parameters

dw

Specifies one or more of the following broadcasting flags:

BSF_ALLOWSFW

Enables the foreground window to be set by the recipient in the Windows 2000 system.

BSF_FLUSHDISK

Flushes the disk after each sent message is processed.

BSF_FORCEIFHUNG

Message is sent even if one or more recipients are hung.

BSF_IGNORECURRENTTASK

Prevents the sending application from receiving its own message.

BSF_NOHANG

Stops broadcasting messages if one recipient is hung.

BSF_NOTIMEOUTIFNOTHUNG

Does not time out unless a recipient is hung.

BSF_POSTMESSAGE

Posts the message instead of sending it.

BSF_QUERY

Each recipient must respond with a True value for the message to be sent to the next recipient.

BSF_SENDNOTIFYMESSAGE

Uses the SendNotifyMessage function to send the message in the Windows 2000 system.

pdw

Specifies one or more of the following flags that determines the recipients of the message:

BSM_ALLCOMPONENTS

Broadcasts to all components in the system

BSM_ALLDESKTOPS

Broadcasts to all desktops in Windows NT/2000 systems

BSM_APPLICATIONS

Broadcasts to all applications

BSM_INSTALLABLEDRIVERS

Broadcasts to installable drivers in Windows 9x systems ...