CallNextHookEx

The CallNextHookEx function passes the hook information to the next hook procedure in the current hook chain. A hook procedure can call this function either before or after processing the hook information.

LRESULT CallNextHookEx(
  HHOOK hhk,      // handle to current hook
  int nCode,      // hook code passed to hook procedure
  WPARAM wParam,  // value passed to hook procedure
  LPARAM lParam   // value passed to hook procedure
);

Parameters

hhk

[in] Handle to the current hook. An application receives this handle as a result of a previous call to the SetWindowsHookEx function.

nCode

[in] Specifies the hook code passed to the current hook procedure. The next hook procedure uses this code to determine how to process the hook information.

wParam

[in] Specifies the wParam value passed to the current hook procedure. The meaning of this parameter depends on the type of hook associated with the current hook chain.

lParam

[in] Specifies the lParam value passed to the current hook procedure. The meaning of this parameter depends on the type of hook associated with the current hook chain.

Return Values

The return value is the value returned by the next hook procedure in the chain. The current hook procedure must also return this value. The meaning of the return value depends on the hook type. For more information, see the descriptions of the individual hook procedures.

Remarks

Hook procedures are installed in chains for particular hook types. CallNextHookEx calls the next hook in the chain.

Calling CallNextHookEx is optional, but it is highly recommended; otherwise, other applications that have installed hooks will not receive hook notifications and may behave incorrectly as a result. You should call CallNextHookEx unless you absolutely need to prevent the notification from being seen by other applications.

Requirements

  Windows NT/2000: Requires Windows NT 3.1 or later.
  Windows 95/98: Requires Windows 95 or later.
  Header: Declared in Winuser.h; include Windows.h.
  Library: Use User32.lib.

See Also

Hooks Overview, Hook Functions, SetWindowsHookEx, UnhookWindowsHookEx