This ObjectType defines a type for files. It is formally defined in Table 1.

Table 1 – FileType

Attribute	Value
BrowseName	FileType
IsAbstract	False
References		NodeClass	BrowseName	DataType	TypeDefinition	ModellingRule
Subtype of the BaseObjectType defined in OPC 10000-5
HasProperty		Variable	Size	UInt64	PropertyType	Mandatory
HasProperty		Variable	Writable	Boolean	PropertyType	Mandatory
HasProperty		Variable	UserWritable	Boolean	PropertyType	Mandatory
HasProperty		Variable	OpenCount	UInt16	PropertyType	Mandatory
HasProperty		Variable	MimeType	String	PropertyType	Optional
HasComponent		Method	Open	Defined in 4.2.2		Mandatory
HasComponent		Method	Close	Defined in 4.2.3		Mandatory
HasComponent		Method	Read	Defined in 4.2.4		Mandatory
HasComponent		Method	Write	Defined in 4.2.5		Mandatory
HasComponent		Method	GetPosition	Defined in 4.2.6		Mandatory
HasComponent		Method	SetPosition	Defined in 4.2.7		Mandatory
HasProperty		Variable	MaxByteStringLength	UInt32	PropertyType	Optional
HasProperty		Variable	LastModifiedTime	DateTime	PropertyType	Optional
Conformance Units
Base Info FileType Base

Size defines the size of the file in Bytes. When a file is opened for write the size might not be accurate. If the Server can not accurately determine the size of the file, the Size Property shall be returned to a Client with a StatusCode of Bad_NotSupported.

Writable indicates whether the file is writable. It does not take any user access rights into account, i.e. although the file is writable this may be restricted to a certain user / user group. The Property does not consider whether the file is currently opened for writing by another client and thus currently locked and not writable by others.

UserWritable indicates whether the file is writable taking user access rights into account. The Property does not consider whether the file is currently opened for writing by another client and thus currently locked and not writable by others.

OpenCount indicates the number of currently valid file handles on the file.

The optional Property MimeType contains the media type of the file based on RFC 2046.

Note that all Methods on a file require a fileHandle, which is returned in the Open Method.

The optional MaxByteStringLength Property indicates the maximum number of bytes of the read and write buffers. If this Property is not present then the maximum size is defined by the MaxByteStringLength Property of the ServerCapabilitiesType defined in OPC 10000-5.

The optional LastModifiedTime Property indicates the time the file was last modified. The Property shall be updated whenever the Server detects that the file has changed.