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.

Syntax

LRESULT CallNextHookEx(      
    HHOOK hhk,
    int nCode,
    WPARAM wParam,
    LPARAM lParam
);

Parameters

hhk

[in] Windows 95/98/ME: Handle to the current hook. An application receives this handle as a result of a previous call to the SetWindowsHookEx function.

Windows NT/XP/2003: Ignored.

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 Value

This value is 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.

Function Information

Minimum DLL Version	user32.dll
Header	Declared in Winuser.h, include Windows.h
Import library	User32.lib
Minimum operating systems	Windows 95, Windows NT 3.1
Unicode	Implemented as Unicode version.

See Also

Hooks Overview, SetWindowsHookEx, UnhookWindowsHookEx