KeUnstackDetachProcess function (ntifs.h)

Article
02/22/2024

The KeUnstackDetachProcess routine detaches the current thread from the address space of a process and restores the previous attach state.

Caution Use this routine with extreme caution. (See the following Remarks section.)

Syntax

void KeUnstackDetachProcess(
  [in] PRKAPC_STATE ApcState
);

Parameters

[in] ApcState

Opaque pointer to a KAPC_STATE structure that was returned from a previous call to KeStackAttachProcess.

Return value

None

Remarks

Every successful call to KeStackAttachProcess must be matched by a subsequent call to KeUnstackDetachProcess.

Note Attaching a thread to a different process can prevent asynchronous I/O operations from completing and can potentially cause deadlocks. In general, the lines of code between the call to KeStackAttachProcess and the call to KeUnstackDetachProcess should be very simple and should not call complex routines or send IRPs to other drivers.

For more information about using system threads and managing synchronization within a nonarbitrary thread context, see Driver Threads, Dispatcher Objects, and Resources.

Requirements

Requirement	Value
Minimum supported client	Windows 2000
Target Platform	Universal
Header	ntifs.h (include Ntifs.h, Fltkernel.h)
Library	NtosKrnl.lib
DLL	NtosKrnl.exe
IRQL	< DISPATCH_LEVEL