KdRefreshDebuggerNotPresent function (wdm.h)

The KdRefreshDebuggerNotPresent macro refreshes the value of the KD_DEBUGGER_NOT_PRESENT global kernel variable.

Syntax

BOOLEAN KdRefreshDebuggerNotPresent();

Return value

KdRefreshDebuggerNotPresent returns the value of KD_DEBUGGER_NOT_PRESENT.

Remarks

When KdRefreshDebuggerNotPresent is called, it forces the value of KD_DEBUGGER_NOT_PRESENT to be updated to reflect whether a kernel debugger is currently attached. This updated value is also used as the return value of this routine.

If a kernel debugger was recently attached or removed, the value of KD_DEBUGGER_NOT_PRESENT may not reflect the new state. If you suspect this has happened, you should call KdRefreshDebuggerNotPresent to refresh the value of this variable. After this call, you may use either the value of KD_DEBUGGER_NOT_PRESENT or the return value of KdRefreshDebuggerNotPresent to determine if the kernel debugger is present.

KD_DEBUGGER_NOT_PRESENT can be modified by Windows or any other kernel-mode binary. Therefore, it is possible that the most recent return value of KdRefreshDebuggerNotPresent may not match the current value of KD_DEBUGGER_NOT_PRESENT.

The following sample shows how to use KdRefreshDebuggerNotPresent:

if (KdRefreshDebuggerNotPresent() == FALSE)
{
    //  A kernel debugger is active.
    DbgPrint("A problem occurred\n");
 DbgBreakPoint();
}
else
{
 //  No kernel debugger attached, or kernel debugging not enabled.
 KeBugCheckEx(...);
}

Requirements

Requirement	Value
Target Platform	Universal
Header	wdm.h (include Wdm.h, Ntddk.h)
Library	NtosKrnl.lib
DLL	NtosKrnl.exe

See also

Determining if a Debugger is Attached

KD_DEBUGGER_ENABLED

KD_DEBUGGER_NOT_PRESENT