#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)

// Environment values

NTSYSCALLAPI
NTSTATUS
NTAPI
NtQuerySystemEnvironmentValue(
    _In_ PUNICODE_STRING VariableName,
    _Out_writes_bytes_(ValueLength) PWSTR VariableValue,
    _In_ USHORT ValueLength,
    _Out_opt_ PUSHORT ReturnLength
    );

#endif
#endif
View code on GitHub

#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwQuerySystemEnvironmentValue(
    _In_ PUNICODE_STRING VariableName,
    _Out_writes_bytes_(ValueLength) PWSTR VariableValue,
    _In_ USHORT ValueLength,
    _Out_opt_ PUSHORT ReturnLength
    );

#endif
View code on GitHub

Seems not works on NT 4.0 SP6. Control Panel applet query and set System Environment values by Rtl...Environment functions or directly by registry.

Documented by

ReactOS
Tomasz Nowak

Requirements

Privilege: SE_SYSTEM_ENVIRONMENT_NAME

NtQuerySystemEnvironmentValue - NtDoc

Documented by

Requirements

See also