NtAllocateVirtualMemoryEx - NtDoc

#ifndef _NTMMAPI_H
// Virtual memory
#if (PHNT_MODE != PHNT_MODE_KERNEL)
#if (PHNT_VERSION >= PHNT_REDSTONE5)

_Must_inspect_result_
_When_(return == 0, __drv_allocatesMem(mem))
NTSYSCALLAPI
NTSTATUS
NTAPI
NtAllocateVirtualMemoryEx(
    _In_ HANDLE ProcessHandle,
    _Inout_ _At_(*BaseAddress, _Readable_bytes_(*RegionSize) _Writable_bytes_(*RegionSize) _Post_readable_byte_size_(*RegionSize)) PVOID *BaseAddress,
    _Inout_ PSIZE_T RegionSize,
    _In_ ULONG AllocationType,
    _In_ ULONG PageProtection,
    _Inout_updates_opt_(ExtendedParameterCount) PMEM_EXTENDED_PARAMETER ExtendedParameters,
    _In_ ULONG ExtendedParameterCount
    );

#endif
#endif
#endif
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#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwAllocateVirtualMemoryEx(
    _In_ HANDLE ProcessHandle,
    _Inout_ _At_(*BaseAddress, _Readable_bytes_(*RegionSize) _Writable_bytes_(*RegionSize) _Post_readable_byte_size_(*RegionSize)) PVOID *BaseAddress,
    _Inout_ PSIZE_T RegionSize,
    _In_ ULONG AllocationType,
    _In_ ULONG PageProtection,
    _Inout_updates_opt_(ExtendedParameterCount) PMEM_EXTENDED_PARAMETER ExtendedParameters,
    _In_ ULONG ExtendedParameterCount
    );

#endif
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