CallWndRetProc
[Now
Supported on Windows NT]
The CallWndRetProc
hook procedure is an application-defined or library-defined callback function
the system calls after the SendMessage function is called. After passing the message
to the destination window procedure, the system passes the message to the hook
procedure. The hook procedure can examine the message; it cannot modify it.
LRESULT CALLBACK CallWndRetProc(
|
int nCode, |
// hook
code |
|
WPARAM wParam, |
//
current-process flag |
|
LPARAM lParam |
// address
of structure with message data |
|
); |
|
Parameters
nCode
Specifies
whether the hook procedure must process the message. If nCode is
HC_ACTION, the hook procedure must process the message. If nCode is less
than zero, the hook procedure must pass the message to the CallNextHookEx function without further
processing and should return the value returned by CallNextHookEx.
wParam
Specifies
whether the message is sent by the current process. If the message is sent by
the current process, it is nonzero; otherwise, it is NULL.
lParam
Points to a CWPRETSTRUCT structure that contains
details about the message.
Return Values
The return
value should be zero.
Remarks
An
application installs the hook procedure by specifying the WH_CALLWNDPROCRET
hook type and the address of the hook procedure in a call to the SetWindowsHookEx
function.
CallWndRetProc is a placeholder for the application-defined or
library-defined function name.
See Also