RtlGetFullPathName_U - NtDoc

#ifndef _NTRTL_H

/**
 * The RtlGetFullPathName_U routine retrieves the full path and file name of the specified file.
 *
 * \param FileName A pointer to the buffer that contains the relative filename.
 * \param BufferLength The length of the buffer for the file path string, in WCHARs. The buffer length must include room for a terminating null character.
 * \param Buffer A pointer to the buffer that receives the file path string.
 * \param FilePart A pointer to a buffer that receives the address (within Buffer) of the final file name component in the path.
 * \return If the function succeeds, the return value specifies the number of characters that are written to the buffer, not including the terminating null character.
 * \sa https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfullpathnamea
 */
NTSYSAPI
ULONG
NTAPI
RtlGetFullPathName_U(
    _In_ PCWSTR FileName,
    _In_ ULONG BufferLength,
    _Out_writes_bytes_(BufferLength) PWSTR Buffer,
    _Out_opt_ PWSTR *FilePart
    );

#endif
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