SIST EN IEC 62541-20:2026

OPC unified architecture - Part 20: File transfer (IEC 62541-20:2025)

This part of IEC 62541, the IEC standards series dedicated to the OPC Unified Architecture, defines an Information Model. The Information Model describes the basic infrastructure to model file transfers.
NOTE In the previous version, File Transfer was in IEC 62541-5:2020, Annex C.

OPC Unified Architecture – Teil 20: Dateiübertragung (IEC 62541-20:2025)

Architecture unifiée OPC - Partie 20: Transfert de fichiers (IEC 62541-20:2025)

IEC 62541-20: 2025 définit un Modèle d'information. Le Modèle d'information décrit l'infrastructure de base pour modéliser les transferts de fichiers.
NOTE Dans la version précédente, le Transfert de fichiers figurait dans l'IEC 62541‑5:2020, Annexe C.

Enotna arhitektura OPC - 20. del: Prenos datotek (IEC 62541-20:2025)

Ta del IEC 62541, serije standardov IEC, namenjene enotni arhitekturi OPC, določa informacijski model. Informacijski model opisuje osnovno infrastrukturo za modeliranje prenosa datotek.
OPOMBA V prejšnji različici je bil prenos datotek v IEC 62541-5:2020, Priloga C.

General Information

• Status: Published
• Public Enquiry End Date: 30-Mar-2024
• Publication Date: 12-Apr-2026
• ICS: 25.040 - Industrial automation systems
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.240.50 - IT applications in industry
• Technical Committee: MOV - Measuring equipment for electromagnetic quantities
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 24-Feb-2026
• Due Date: 01-May-2026
• Completion Date: 13-Apr-2026
• Ref Project: EN IEC 62541-20:2026 - OPC unified architecture - Part 20: File transfer

Relations

• Refers: SIST EN IEC 62541-1:2026 - OPC unified architecture - Part 1: Overview and concepts (IEC 62541-1:2025)
• Effective Date: 03-Feb-2026
• Refers: SIST EN IEC 62541-5:2026 - OPC unified architecture - Part 5: Information model (IEC 62541-5:2026)
• Effective Date: 03-Feb-2026
• Refers: SIST EN IEC 62541-3:2020 - OPC unified architecture - Part 3: Address Space Model (IEC 62541-3:2020)
• Effective Date: 03-Feb-2026
• Refers: SIST EN IEC 62541-4:2020 - OPC Unified Architecture - Part 4: Services (IEC 62541-4:2020)
• Effective Date: 03-Feb-2026
• Refers: SIST EN IEC 62541-4:2026 - OPC unified architecture - Part 4: Services (IEC 62541-4:2025)
• Effective Date: 03-Feb-2026
• Refers: SIST EN IEC 62541-5:2020 - OPC Unified Architecture - Part 5: Information Model
• Effective Date: 03-Feb-2026
• Refers: SIST EN IEC 62541-3:2026 - OPC unified architecture - Part 3: Address space model (IEC 62541-3:2025)
• Effective Date: 03-Feb-2026
• Referred By: SIST EN 62769-7:2015 - Devices and integration in enterprise systems; Field Device Integration - Part 7: Communication Devices (IEC 62769-7:2015)
• Effective Date: 20-Feb-2026
• Referred By: SIST EN IEC 62769-6:2021 - Field Device Integration (FDI) - Part 6: Technology Mapping (IEC 62769-6:2021
• Effective Date: 20-Feb-2026
• Referred By: SIST EN IEC 62769-7:2021 - Field Device Integration (FDI) - Part 7: Communication devices (IEC 62769-7:2021)
• Effective Date: 20-Feb-2026
• Referred By: SIST EN 62769-3:2015 - Devices and integration in enterprise systems; Field Device Integration - Part 3: FDI Server (IEC 62769-3:2015)
• Effective Date: 20-Feb-2026
• Referred By: SIST EN IEC 62769-1:2023 - Field Device Integration (FDI®) - Part 1: Overview (IEC 62769-1:2023)
• Effective Date: 20-Feb-2026
• Referred By: SIST EN 62769-1:2015 - Devices and integration in enterprise systems; Field Device Integration - Part 1: Overview (IEC 62769-1:2015)
• Effective Date: 20-Feb-2026
• Referred By: SIST EN 62769-6:2015 - Devices and integration in enterprise systems; Field Device Integration - Part6: Technology Mapping (IEC 62769-6:2015)
• Effective Date: 20-Feb-2026
• Referred By: SIST EN IEC 62541-14:2026 - OPC unified architecture - Part 14: Pubsub (IEC 62541-14:2026)
• Effective Date: 10-Feb-2026

Overview

SIST EN IEC 62541-20:2026, titled OPC Unified Architecture – Part 20: File Transfer, is a European Standard developed by CLC and approved by CENELEC. This standard is part of the larger IEC 62541 OPC Unified Architecture (UA) series, which addresses interoperability in industrial automation and enterprise systems. The scope of SIST EN IEC 62541-20:2026 is to define an information model specifically for file transfer, establishing a standardized approach for representing and managing file and file system-related data within OPC UA environments.

This standard consolidates and enhances prior OPC UA file transfer specifications, providing a robust infrastructure for secure, efficient, and flexible file transfers in industrial and IT applications.

Key Topics

• Information Model for File Transfer
  SIST EN IEC 62541-20:2026 defines an OPC UA-based information model that enables systems to represent and conduct file transfers efficiently. Files are modeled as Objects, with methods for reading, writing, opening, closing, and handling positions within files.

• File and Directory Management

  • FileType: Describes an object representing a file with standard properties such as Size, Writable, UserWritable, and MimeType.
  • FileDirectoryType: Models directories, allowing organization of files and subdirectories in a hierarchical structure.
  • Methods such as CreateDirectory, CreateFile, Delete, and MoveOrCopy enable dynamic file system management.

• Temporary File Transfers The standard outlines support for temporary files and specific workflows (handshakes) for scenarios such as configuration uploads or firmware updates, using the TemporaryFileTransferType.

• Session-Scoped File Handles File access is governed by handles linked to user sessions, providing security and consistency for concurrent file operations.

• Conformance with the OPC UA Series This standard builds upon and references other parts of IEC 62541, particularly concerning address space modeling and service definitions.

Applications

SIST EN IEC 62541-20:2026 delivers significant practical value across various industries:

• Industrial Automation
  Facilitates the secure, standardized transfer of configuration files, firmware updates, production recipes, and logs between devices, servers, and clients within industrial process environments.

• Device and System Integration
  OEMs and system integrators benefit from uniform methods to exchange files across heterogeneous systems, reducing development complexity and improving reliability.

• IT-OT Convergence
  Supports IT applications in industries by providing a bridge between operational technology (OT) assets and enterprise information systems, particularly for managing digital assets and ensuring auditability.

• Remote and Distributed Operations
  Enables reliable file transfer in distributed automation landscapes, supporting remote diagnostics, asset management, and secure data exchange.

Related Standards

SIST EN IEC 62541-20:2026 is part of a comprehensive suite of OPC UA standards and is closely related to:

• EN IEC 62541-1 - OPC Unified Architecture – Part 1: Overview and Concepts
• EN IEC 62541-3 - OPC Unified Architecture – Part 3: Address Space Model
• EN IEC 62541-4 - OPC Unified Architecture – Part 4: Services
• EN IEC 62541-5 - OPC Unified Architecture – Part 5: Information Model
  (Note: In earlier versions, file transfer specifications were included as Annex C of Part 5.)

For the most efficient implementation of OPC UA file transfer, organizations should also consult these core OPC UA documents.

Keywords: OPC UA, IEC 62541-20, file transfer, industrial automation, file management, file system model, information model, OPC Unified Architecture, directory management, industrial IT applications.

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2026
Enotna arhitektura OPC - 20. del: Prenos datotek (IEC 62541-20:2025)
OPC unified architecture - Part 20: File transfer (IEC 62541-20:2025)
OPC Unified Architecture – Teil 20: Dateiübertragung (IEC 62541-20:2025)
Architecture unifiée OPC - Partie 20: Transfert de fichiers (IEC 62541-20:2025)
Ta slovenski standard je istoveten z: EN IEC 62541-20:2026
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.240.50 Uporabniške rešitve IT v IT applications in industry
industriji
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 62541-20

NORME EUROPÉENNE
EUROPÄISCHE NORM February 2026
ICS 25.040
English Version
OPC unified architecture - Part 20: File transfer
(IEC 62541-20:2025)
Architecture unifiée OPC - Partie 20: Transfert de fichiers OPC Unified Architecture - Teil 20: Dateiübertragung
(IEC 62541-20:2025) (IEC 62541-20:2025)
This European Standard was approved by CENELEC on 2026-01-26. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62541-20:2026 E

European foreword
The text of document 65E/1045/CDV, future edition 1 of IEC 62541-20, prepared by SC 65E "Devices
and integration in enterprise systems" of IEC/TC 65 "Industrial-process measurement, control and
automation" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2027-02-28
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2029-02-28
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 62541-20:2025 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 62541-5:2020 NOTE Approved as EN IEC 62541-5:2020 (not modified)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 62541-1 - OPC Unified Architecture - Part 1: EN IEC 62541-1 -
Overview and concepts
IEC 62541-3 - OPC Unified Architecture - Part 3: Address EN IEC 62541-3 -
Space Model
IEC 62541-4 - OPC unified architecture - Part 4: Services EN IEC 62541-4 -
IEC 62541-5 - OPC Unified architecture - Part 5: EN IEC 62541-5 -
Information Model
IEC 62541-20 ®
Edition 1.0 2025-12
INTERNATIONAL
STANDARD
OPC unified architecture -
Part 20: File transfer
ICS 25.040  ISBN 978-2-8327-0836-1

IEC 62541-20:2025-12(en)
IEC 62541-20:2025 © IEC 2025
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
3.1 Terms and definitions. 5
4 File transfer model . 5
4.1 Overview . 5
4.2 FileType . 6
4.2.1 General . 6
4.2.2 Open . 7
4.2.3 Close . 8
4.2.4 Read . 9
4.2.5 Write . 10
4.2.6 GetPosition . 11
4.2.7 SetPosition . 11
4.3 File system . 12
4.3.1 FileDirectoryType . 12
4.3.2 FileSystem Object . 13
4.3.3 CreateDirectory . 13
4.3.4 CreateFile. 14
4.3.5 Delete . 15
4.3.6 MoveOrCopy . 16
4.4 Temporary file transfer . 17
4.4.1 TemporaryFileTransferType . 17
4.4.2 File transfer sequences . 18
4.4.3 GenerateFileForRead . 18
4.4.4 GenerateFileForWrite . 19
4.4.5 CloseAndCommit . 20
4.4.6 FileTransferStateMachineType . 21
4.4.7 Reset . 25
Bibliography . 26

Figure 1 – FileSystem example . 13
Figure 2 – Read file transfer example sequence . 18
Figure 3 – Write file transfer example sequence . 18
Figure 4 – File transfer States . 21
Figure 5 – FileTransferStateMachineType . 22

Table 1 – FileType . 6
Table 2 – Open Method AddressSpace definition . 8
Table 3 – Close Method AddressSpace definition . 9
Table 4 – Read Method AddressSpace definition . 10
Table 5 – Write Method AddressSpace definition . 10
Table 6 – GetPosition Method AddressSpace definition . 11
Table 7 – SetPosition Method AddressSpace definition . 12
IEC 62541-20:2025 © IEC 2025
Table 8 – FileDirectoryType . 12
Table 9 – CreateDirectory Method AddressSpace definition . 14
Table 10 – CreateFile Method AddressSpace definition . 15
Table 11 – Delete Method AddressSpace definition . 16
Table 12 – MoveOrCopy Method AddressSpace definition . 17
Table 13 – TemporaryFileTransferType . 17
Table 14 – GenerateFileForRead Method AddressSpace definition . 19
Table 15 – GenerateFileForWrite Method AddressSpace definition . 20
Table 16 – CloseAndCommit Method AddressSpace definition . 21
Table 17 – FileTransferStateMachineType . 23
Table 18 – FileTransferStateMachineType Attribute values for child Nodes . 23
Table 19 – FileTransferStateMachineType Additional References . 24
Table 20 – Reset Method AddressSpace definition . 25

IEC 62541-20:2025 © IEC 2025
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPC unified architecture -
Part 20: File Transfer
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 62541-20 has been prepared by subcommittee 65E: Devices and integration in enterprise
systems, of IEC technical committee 65: Industrial-process measurement, control and
automation. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
65E/1045/CDV 65E/1102/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
IEC 62541-20:2025 © IEC 2025
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
Throughout this document and the other Parts of the series, certain document conventions are
used:
Italics are used to denote a defined term or definition that appears in the "Terms and definitions"
clause in one of the parts of the series.
Italics are also used to denote the name of a service input or output parameter or the name of
a structure or element of a structure that are usually defined in tables.
The italicized terms and names are also often written in camel-case (the practice of writing
compound words or phrases in which the elements are joined without spaces, with each
element's initial letter capitalized within the compound). For example, the defined term is
AddressSpace instead of Address Space. This makes it easier to understand that there is a
single definition for AddressSpace, not separate definitions for Address and Space.
A list of all parts in the IEC 62541 series, published under the general title OPC Unified
Architecture, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
IEC 62541-20:2025 © IEC 2025
1 Scope
This part of IEC 62541, the IEC standards series dedicated to the OPC Unified Architecture,
defines an Information Model. The Information Model describes the basic infrastructure to
model file transfers.
NOTE In the previous version, File Transfer was in IEC 62541-5:2020, Annex C.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 62541-1, OPC Unified Architecture - Part 1: Overview and Concepts
IEC 62541-3, OPC Unified Architecture - Part 3: Address Space Model
IEC 62541-4, OPC Unified Architecture - Part 4: Services
IEC 62541-5, OPC Unified Architecture - Part 5: Information Model
3 Terms and definitions
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62541-1, IEC 62541-3
and IEC 62541-5 apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
4 File transfer model
4.1 Overview
This document describes an information model for file transfer. Files could be modelled in OPC
UA as simple Variables using ByteStrings. However, the overall message size in OPC UA is
limited due to resources and security issues (denial of service attacks). Only accessing parts
of the array can lead to concurrency issues if one client is reading the array while others are
manipulating it. Therefore, the ObjectType FileType is defined representing a file with Methods
to access the file. The life-cycle of a file stored on a hard disk and an instance of the FileType
representing the file in an OPC UA AddressSpace can be independent.
In addition to representing individual files this document also defines a way to represent a whole
file system or a part of a file system. This can be done using the FileDirectoryType in
combination with the FileType. The FileDirectoryType provides Methods to create, delete, and
move files and directories. The root of a file system or part of a file system is represented by
an instance of the FileDirectoryType with the BrowseName FileSystem. All directories below
the root directory are represented by instances of the FileDirectoryType or a subtype. All files
below the root directory are represented by instances of the FileType or a subtype.
IEC 62541-20:2025 © IEC 2025
In different situations like transfer of configuration files or firmware update, the files are
temporary, and an additional handshake is necessary to create the file for reading or to apply
the file after writing it to the server. This use case is covered by the TemporaryFileTransferType
defined in this document.
4.2 FileType
4.2.1 General
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 Modelling Rule
Subtype of the BaseObjectType defined in IEC 62541-5
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 can 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.
IEC 62541-20:2025 © IEC 2025
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 IEC 62541-5.
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.
4.2.2 Open
Open is used to open a file represented by an Object of FileType. When a client opens a file it
gets a file handle that is valid while the session is open. Clients shall use the Close Method to
release the handle when they do not need access to the file anymore. Clients can open the
same file several times for read. A request to open for writing shall return Bad_NotWritable
when the file is already opened. A request to open for reading shall return Bad_NotReadable
when the file is already opened for writing.
Signature
Open(
[in] Byte mode
[out] UInt32 fileHandle
);
Argument Description
mode Indicates whether the file should be opened only for read operations or for read and
write operations and where the initial position is set.
The mode is an 8-bit unsigned integer used as bit mask with the structure defined as
follows:
Bit 0 – "Read" - The file is opened for reading. If this bit is not set the Read
Method cannot be executed.
Bit 1 – "Write" - The file is opened for writing. If this bit is not set the Write
Method cannot be executed.
Bit 2 – "EraseExisting" - This bit can only be set if the file is opened for writing
(Write bit is set). The existing content of the file is erased
and an empty file is provided.
Bit 3 – "Append" - When the Append bit is set the file is opened at end of the
file, otherwise at begin of the file. The SetPosition Method
can be used to change the position.
Bit 4-7 – "Reserved" - Reserved for future use. Shall always be zero.
Field Bit Description
Read 0 The file is opened for reading. If this bit is not set the
Read Method cannot be executed.
Write 1 The file is opened for writing. If this bit is not set the Write
Method cannot be executed.
EraseExisting 2 This bit can only be set if the file is opened for writing
(Write bit is set). The existing content of the file is erased
and an empty file is provided.
Append 3 When the Append bit is set the file is opened at end of
the file, otherwise at begin of the file. The SetPosition
Method can be used to change the position.
Reserved 4:7 Reserved for future use. Shall always be zero.
fileHandle A handle for the file used in other method calls indicating not the file (this is done by
the Object of the Method call) but the access request and thus the position in the
file. The fileHandle is generated by the server and is unique for the Session. Clients
cannot transfer the fileHandle to another Session but shall get a new fileHandle by
calling the Open Method.
IEC 62541-20:2025 © IEC 2025
Method Result Codes (defined in Call Service)
Result Code Description
Bad_NotReadable IEC 62541-4 defines a base definition for this code. File might be locked and thus not
readable.
Bad_NotWritable IEC 62541-4 defines a base definition for this code.
Bad_InvalidState IEC 62541-4 defines a base definition for this code. The file is locked and thus not
writable.
Bad_InvalidArgument IEC 62541-4 defines a base definition for this code. Mode setting is invalid.
Bad_NotFound IEC 62541-4 defines a base definition for this code.
Bad_UnexpectedError IEC 62541-4 defines a base definition for this code.

Table 2 specifies the AddressSpace representation for the Open Method.
Table 2 – Open Method AddressSpace definition
Attribute Value
BrowseName Open
References NodeClass BrowseName DataType TypeDefinition ModellingRule
HasProperty Variable InputArguments Argument[] PropertyType Mandatory
HasProperty Variable OutputArguments Argument[] PropertyType Mandatory
Conformance Units
Base Info FileType Base
4.2.3 Close
Close is used to close a file represented by a FileType. When a client closes a file, the handle
becomes invalid.
Signature
Close(
[in] UInt32 fileHandle
);
Argument Description
fileHandle A handle indicating the access request and thus indirectly the position inside the file.

Method Result Codes (defined in Call Service)
Result Code Description
Bad_InvalidArgument IEC 62541-4 defines a base definition for this code. Invalid file handle in call.
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