#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)

/**
 * The NtDeleteAtom routine releases one caller-owned ordinary string-atom reference. The table entry is
 * removed when its unpinned reference count reaches zero; identifiers may be reused.
 *
 * \param Atom A 16-bit atom identifier, not an object handle. Balance additions,
 * not lookups, and do not delete references owned by unrelated code.
 * \return NTSTATUS. Integer atoms 1 through 0xBFFF return STATUS_SUCCESS without
 * removing a string entry. Zero or an invalid string identifier returns
 * STATUS_INVALID_HANDLE. A pinned string entry returns
 * informational STATUS_WAS_LOCKED (0x40000019) without being decremented or removed.
 * \remarks NT_SUCCESS does not prove that an entry disappeared. Other references,
 * pinning and lowbox accounting can retain it. The pin/saturation paths are distinct
 * from the ordinary balanced-add/delete lifetime.
 * \see https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-globaldeleteatom
 */
_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
NtDeleteAtom(
    _In_ RTL_ATOM Atom
    );

#endif
#endif
View code on GitHub

#ifndef _NTZWAPI_H

_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
ZwDeleteAtom(
    _In_ RTL_ATOM Atom
    );

#endif
View code on GitHub