NtQueryBootOptions - NtDoc

#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)
#if (PHNT_VERSION >= PHNT_WINXP)

NTSYSCALLAPI
NTSTATUS
NTAPI
NtQueryBootOptions(
    _Out_writes_bytes_opt_(*BootOptionsLength) PBOOT_OPTIONS BootOptions,
    _Inout_ PULONG BootOptionsLength
    );

#endif
#endif
#endif
View code on GitHub

#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwQueryBootOptions(
    _Out_writes_bytes_opt_(*BootOptionsLength) PBOOT_OPTIONS BootOptions,
    _Inout_ PULONG BootOptionsLength
    );

#endif
View code on GitHub