ISO/IEC 23360-1-3:2021

INTERNATIONAL ISO/IEC
STANDARD 23360-1-3
First edition
2021-10
Linux Standard Base (LSB) —
Part 1-3:
Desktop specification generic part
Reference number
©
ISO/IEC 2021
© ISO/IEC 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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ii © ISO/IEC 2021 – All rights reserved

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical activity.
ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of document should be noted (see www.iso.org/directives or
www.iec.ch/members_experts/refdocs).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights. Details
of any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents) or the IEC list of patent
declarations received (see patents.iec.ch).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the World
Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT),
see www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by the Linux Foundation as Linux Standard Base (LSB): Desktop
specification generic part and drafted in accordance with its editorial rules. It was assigned to Joint
Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee SC 22, Programming
languages, their environments and system software interfaces, and adopted by National Bodies.
This first edition of ISO/IEC 23360-1-3 cancels and replaces ISO/IEC 23360-1:2006, which has been
technically revised.
This document is based on “The GNU Free Documentation License, version 1.1”. The license is available
at https://www.gnu.org/licenses/old-licenses/fdl-1.1.html.
A list of all parts in the ISO/IEC 23660 series can be found on the ISO and IEC websites.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html and www.iec.ch/national-
committees.
© ISO/IEC 2021 – All rights reserved iii

Contents
Foreword . iii
Introduction .viii
I Introductory Elements . 1
1 Scope . 2
2 References . 3
2.1 Normative References . 3
2.2 Informative References/Bibliography. 6
3 Requirements . 7
3.1 Relevant Libraries . 7
4 Terms and Definitions . 9
5 Documentation Conventions . 11
II Graphic Libraries . 12
6 Libraries . 13
6.1 Interfaces for libX11 . 13
6.2 Data Definitions for libX11 . 23
6.3 Interface Definitions for libX11 . 180
6.4 Interfaces for libSM. 180
6.5 Data Definitions for libSM. 181
6.6 Interfaces for libICE . 185
6.7 Data Definitions for libICE . 187
6.8 Interface Definitions for libICE . 194
6.9 Interfaces for libXt. 196
6.10 Data Definitions for libXt . 201
6.11 Interface Definitions for libXt . 235
6.12 Interfaces for libXext . 236
6.13 Data Definitions for libXext . 239
6.14 Interface Definitions for libXext . 257
6.15 Interfaces for libXi . 257
6.16 Data Definitions for libXi . 258
6.17 Interfaces for libXtst . 288
6.18 Data Definitions for libXtst . 289
6.19 Interfaces for libxcb . 290
6.20 Data Definitions for libxcb . 298
6.21 Interface Definitions for libxcb . 373
III OpenGL Libraries . 374
7 Libraries . 375
7.1 Interfaces for libGL . 375
7.2 Data Definitions for libGL . 384
7.3 Interfaces for libGLU . 438
7.4 Data Definitions for libGLU . 439
IV PNG12 library . 445
8 Libraries . 446
8.1 Interfaces for libpng12 . 446
8.2 Data Definitions for libpng12 . 448
8.3 Interface Definitions for libpng12 . 462
V JPEG library . 527
9 Libraries . 528
9.1 Interfaces for libjpeg . 528
iv © 2021 ISO/IEC – All rights reserved

9.2 Data Definitions for libjpeg . 529
9.3 Interface Definitions for libjpeg . 539
VI Fontconfig library . 561
10 Libraries . 562
10.1 Interfaces for libfontconfig . 562
10.2 Data Definitions for libfontconfig . 565
11 Commands and Utilities . 574
11.1 Commands and Utilities . 574
11.2 Command Behavior . 574
VII Freetype library . 577
12 Libraries . 578
12.1 Interfaces for libfreetype . 578
12.2 Data Definitions for libfreetype . 580
12.3 Interface Definitions for libfreetype . 610
VIII Xft library . 612
13 Libraries . 613
13.1 Interfaces for libXft . 613
13.2 Data Definitions for libXft . 614
13.3 Interface Definitions for libXft . 619
IX Xrender library . 620
14 Libraries . 621
14.1 Interfaces for libXrender . 621
14.2 Data Definitions for libXrender . 622
14.3 Interface Definitions for libXrender . 629
X Cairo Vector Graphics library . 630
15 Libraries . 631
15.1 Interfaces for libcairo . 631
15.2 Data Definitions for libcairo . 638
15.3 Interface Definitions for libcairo . 665
XI tiff library . 666
16 Libraries . 667
16.1 Interfaces for libtiff . 667
16.2 Data Definitions for libtiff . 669
XII GTK+ Stack Libraries . 683
17 Libraries . 684
17.1 Introduction . 684
17.2 Interfaces for libglib-2.0 . 685
17.3 Data Definitions for libglib-2.0 . 726
17.4 Interface Definitions for libglib-2.0 . 795
17.5 Interfaces for libgmodule-2.0 . 796
17.6 Data Definitions for libgmodule-2.0 . 796
17.7 Interfaces for libgobject-2.0 . 797
17.8 Data Definitions for libgobject-2.0 . 810
17.9 Interface Definitions for libgobject-2.0 . 848
17.10 Interfaces for libgthread-2.0 . 849
17.11 Interfaces for libgio-2.0 . 850
17.12 Data Definitions for libgio-2.0 . 887
17.13 Interface Definitions for libgio-2.0 . 1048
17.14 Interfaces for libatk-1.0 . 1048
17.15 Data Definitions for libatk-1.0 . 1054
© 2021 ISO/IEC – All rights reserved v

17.16 Interface Definitions for libatk-1.0 . 1079
17.17 Interfaces for libpango-1.0 . 1079
17.18 Data Definitions for libpango-1.0 . 1088
17.19 Interfaces for libpangocairo-1.0 . 1111
17.20 Data Definitions for libpangocairo-1.0 . 1113
17.21 Interfaces for libpangoxft-1.0 . 1114
17.22 Data Definitions for libpangoxft-1.0 . 1115
17.23 Interfaces for libpangoft2-1.0 . 1117
17.24 Data Definitions for libpangoft2-1.0 . 1119
17.25 Interfaces for libgdk_pixbuf-2.0 . 1121
17.26 Data Definitions for libgdk_pixbuf-2.0 . 1125
17.27 Interfaces for libgdk_pixbuf_xlib-2.0 . 1133
17.28 Data Definitions for libgdk_pixbuf_xlib-2.0 . 1134
17.29 Interfaces for libgdk-x11-2.0 . 1136
17.30 Data Definitions for libgdk-x11-2.0 . 1149
17.31 Interfaces for libgtk-x11-2.0 . 1210
17.32 Data Definitions for libgtk-x11-2.0 . 1272
17.33 Interface Definitions for libgtk-x11-2.0 . 1479
XIII Qt Libraries . 1482
18 Libraries . 1483
18.1 Introduction . 1483
18.2 Interfaces for libQtCore . 1484
18.3 Data Definitions for libQtCore . 1578
18.4 Interface Definitions for libQtCore . 1620
18.5 Interfaces for libQtGui . 1628
18.6 Data Definitions for libQtGui . 2163
18.7 Interface Definitions for libQtGui . 2209
18.8 Interfaces for libQtXml . 2267
18.9 Data Definitions for libQtXml . 2288
18.10 Interfaces for libQtOpenGL . 2289
18.11 Data Definitions for libQtOpenGL . 2300
18.12 Interface Definitions for libQtOpenGL . 2301
18.13 Interfaces for libQtSql . 2302
18.14 Data Definitions for libQtSql . 2325
18.15 Interface Definitions for libQtSql . 2327
18.16 Interfaces for libQtSvg. 2328
18.17 Data Definitions for libQtSvg. 2334
18.18 Interfaces for libQtNetwork . 2335
18.19 Data Definitions for libQtNetwork . 2356
18.20 Interface Definitions for libQtNetwork . 2360
XIV ALSA sound library . 2362
19 Libraries . 2363
19.1 Interfaces for libasound . 2363
19.2 Data Definitions for libasound . 2386
XV Desktop Environment . 2429
20 Desktop Environment . 2430
20.1 Desktop Base Directory. 2430
20.2 Desktop Entries . 2430
20.3 Desktop Menu Specification . 2430
20.4 Icon Theme Specification . 2430
vi © 2021 ISO/IEC – All rights reserved

21 Desktop Commands . 2431
21.1 Xdg-utils . 2431
XVI Package Format and Installation . 2432
22 Software Installation . 2433
22.1 Package Dependencies . 2433
Annex A Alphabetical Listing of Interfaces by Library . 2434
A.1 libGL . 2434
A.2 libGLU . 2444
A.3 libICE . 2445
A.4 libSM . 2446
A.5 libX11 . 2447
A.6 libXext . 2458
A.7 libXft . 2460
A.8 libXi . 2461
A.9 libXrender . 2462
A.10 libXt . 2463
A.11 libXtst. 2468
A.12 libcairo . 2468
A.13 libcairo-gobject . 2475
A.14 libcairo-script-interpreter . 2476
A.15 libfontconfig. 2476
A.16 libfreetype . 2479
A.17 libjpeg . 2481
A.18 libpng12 . 2482
A.19 libtiff . 2485
A.20 libxcb . 2487
A.21 libatk-1.0 . 2496
A.22 libgdk-x11-2.0 . 2500
A.23 libgdk_pixbuf-2.0 . 2510
A.24 libgdk_pixbuf_xlib-2.0 . 2513
A.25 libgio-2.0 . 2514
A.26 libglib-2.0 . 2546
A.27 libgmodule-2.0 . 2570
A.28 libgobject-2.0 . 2570
A.29 libgthread-2.0 . 2578
A.30 libgtk-x11-2.0 . 2578
A.31 libpango-1.0 . 2628
A.32 libpangocairo-1.0 . 2635
A.33 libpangoft2-1.0 . 2636
A.34 libpangoxft-1.0 . 2637
A.35 libQtCore . 2637
A.36 libQtGui . 2687
A.37 libQtNetwork. 2887
A.38 libQtOpenGL . 2898
A.39 libQtSql . 2904
A.40 libQtSvg . 2913
A.41 libQtXml . 2915
A.42 libasound . 2925
© 2021 ISO/IEC – All rights reserved vii

Introduction
The LSB defines a binary interface for application programs that are compiled
and packaged for LSB-conforming implementations on many different hardware
architectures. A binary specification must include information specific to the
computer processor architecture for which it is intended. To avoid the complexity
of conditional descriptions, the specification has instead been divided into
generic parts which are augmented by one of several architecture-specific parts,
depending on the target processor architecture; the generic part will indicate
when reference must be made to the architecture part, and vice versa.
This document should be used in conjunction with the documents it references.
This document enumerates the system components it includes, but descriptions
of those components may be included entirely or partly in this document, partly
in other documents, or entirely in other reference documents. For example, the
section that describes system service routines includes a list of the system
routines supported in this interface, formal declarations of the data structures
they use that are visible to applications, and a pointer to the underlying
referenced specification for information about the syntax and semantics of each
call. Only those routines not described in standards referenced by this document,
or extensions to those standards, are described in the detail. Information
referenced in this way is as much a part of this document as is the information
explicitly included here.
The specification carries a version number of either the form x.y or x.y.z. This
version number carries the following meaning:
1. The first number (x) is the major version number. Versions sharing the same
major version number shall be compatible in a backwards direction; that is,
a newer version shall be compatible with an older version. Any deletion of
a library results in a new major version number. Interfaces marked as
deprecated may be removed from the specification at a major version
change.
2. The second number (y) is the minor version number. Libraries and
individual interfaces may be added, but not removed. Interfaces may be
marked as deprecated at a minor version change. Other minor changes may
be permitted at the discretion of the LSB workgroup.
3. The third number (z), if present, is the editorial level. Only editorial changes
should be included in such versions.
Since this specification is a descriptive Application Binary Interface, and not a
source level API specification, it is not possible to make a guarantee of 100%
backward compatibility between major releases. However, it is the intent that
those parts of the binary interface that are visible in the source level API will
remain backward compatible from version to version, except where a feature
marked as "Deprecated" in one release may be removed from a future release.
Implementors are strongly encouraged to make use of symbol versioning to
permit simultaneous support of applications conforming to different releases of
this specification.
LSB is a trademark of the Linux Foundation. Developers of applications or
implementations interested in using the trademark should see the Linux
Foundation Certification Policy for details.
viii © 2021 ISO/IEC – All rights reserved

I Introductory Elements
© 2021 ISO/IEC – All rights reserved 1

1 Scope
The Linux Standard Base (LSB) defines a system interface for compiled
applications and a minimal environment for support of installation scripts. Its
purpose is to enable a uniform industry standard environment for high-volume
applications conforming to the LSB.
These specifications are composed of two basic parts: a common part describing
those parts of the interface that remain constant across all implementations of the
LSB, and an architecture-specific part describing the parts of the interface that
vary by processor architecture. Together, the common part and the relevant
architecture-specific part for a single hardware architecture provide a complete
interface specification for compiled application programs on systems that share
a common hardware architecture.
The LSB contains both a set of Application Program Interfaces (APIs) and
Application Binary Interfaces (ABIs). APIs may appear in the source code of
portable applications, while the compiled binary of that application may use the
larger set of ABIs. A conforming implementation provides all of the ABIs listed
here. The compilation system may replace (e.g. by macro definition) certain APIs
with calls to one or more of the underlying binary interfaces, and may insert calls
to binary interfaces as needed.
The LSB is primarily a binary interface definition. Not all of the source level APIs
available to applications may be contained in this specification.
This is the common part of the Desktop module of the Linux Standard Base (LSB).
This module provides the fundamental system interfaces, libraries, and runtime
environment upon which all conforming applications and libraries depend
requiring the LSB Desktop module depend.
The common part of LSB Desktop should be used in conjunction with an
architecture-specific part. Whenever a section of the common part is
supplemented by architecture-specific information, the common part includes a
reference to the architecture-specific part. Architecture-specific parts of LSB
Desktop may also contain additional information that is not referenced in the
common part.
Interfaces described in this part of LSB Desktop are mandatory except where
explicitly listed otherwise. Interfaces described in the LSB Desktop module
supplement those described in the LSB Core module. They do not depend on
other LSB modules.
2 © 2021 ISO/IEC – All rights reserved

2 References
2.1 Normative References
The specifications listed below are referenced in whole or in part by the LSB
Desktop specification. Such references may be normative or informative; a
reference to specification shall only be considered normative if it is explicitly cited
as such. The LSB Desktop specification may make normative references to a
portion of these specifications (that is, to define a specific function or group of
functions); in such cases, only the explicitly referenced portion of the specification
is to be considered normative.
Table 2-1 Normative References
Name Title URL
ATK 2.2.0 Reference ATK 2.2.0 Reference http://developer.gnom
Manual Manual e.org/atk/2.2/index.ht
ml
Double Buffer Double Buffer http://refspecs.linux-
Extension Library Extension Library - foundation.org/X11/db
Protocol Version 1.0 elib.pdf
Fontconfig Developers Fontconfig Developers http://refspecs.linuxfo
Reference Reference, Version 2.6.0 undation.org/fontconfi
g-2.6.0
Gdk 2.10.14 Reference Gdk 2.10.14 Reference http://library.gnome.o
Manual Manual rg/devel/gdk/2.10/
Gdk-pixbuf 2.26.0 Gdk-pixbuf 2.26.0 http://developer.gnom
Reference Manual Reference Manual e.org/gdk-pixbuf/2.26
Gio 2.32 Reference Gio 2.32 Reference http://developer.gnom
Manual Manual e.org/gio/2.32
Glib 2.32 Reference Glib 2.32 Reference http://developer.gnom
Manual Manual e.org/glib/2.32
Gobject 2.32 Reference Gobject 2.32 Reference http://developer.gnom
Manual Manual e.org/gobject/2.32
Gtk+ 2.10.14 Reference Gtk+ 2.10.14 Reference http://library.gnome.o
Manual Manual rg/devel/gtk/2.10/
ISO C (1999) ISO/IEC 9899:1999 -
Programming
Languages -- C
ISO/IEC 14882: 2003 ISO/IEC 14882: 2003
C++ Language Programming
languages --C++
Itanium™ C++ ABI Itanium™ C++ ABI http://refspecs.linuxfo
(Revision 1.86) undation.org/cxxabi-
1.86.html
Libtiff 4.0.2 Reference Libtiff 4.0.2 Reference http://www.libtiff.org
Manual Manual /man/index.html
© 2021 ISO/IEC – All rights reserved 3

Name Title URL
Libxcb API Libxcb API http://xcb.freedesktop.
org/XcbApi/
The OpenGL® http://www.opengl.or
OpenGL 2.1
Graphics System: A g/registry/doc/glspec2
Specification (Version 1.20061201.pdf
2.1)
OpenGL ABI OpenGL® Application http://www.opengl.or
Binary Interface for g/registry/ABI/
Linux
OpenGL Extensions OpenGL® Graphics http://opengl.org/doc
with the X Window umentation/specs/glx/
System® (Version 1.3) glx1.3.pdf
OpenGL Utilities The OpenGL Graphics http://www.opengl.or
System Utility Library g/documentation/spec
(Version 1.3) s/glu/glu1_3.pdf
Pango 1.30.1 Reference Pango 1.30.1 Reference http://developer.gnom
Manual Manual e.org/pango/1.30/inde
x.html
POSIX 1003.1-2008 Portable Operating http://www.unix.org/
(ISO/IEC 9945-2009) System Interface version4/
(POSIX®) 2008 Edition
/ The Open Group
Technical Standard
Base Specifications,
Issue 7
QtCore 4.2.0 Qt 4.2.0 Reference http://doc.qt.digia.com
Manual /4.2/qtcore.html
QtGui 4.2.0 Qt 4.2.0 Reference http://doc.qt.digia.com
Manual /4.2/qtgui.html
QtNetwork 4.2.0 Qt 4.2.0 Reference http://doc.qt.digia.com
Manual /4.2/qtnetwork.html
QtOpenGL 4.2.0 Qt 4.2.0 Reference http://doc.qt.digia.com
Manual /4.2/qtopengl.html
QtSql 4.2.0 Qt 4.2.0 Reference http://doc.qt.digia.com
Manual /4.2/qtsql.html
QtSvg 4.2.0 Qt 4.2.0 Reference http://doc.qt.digia.com
Manual /4.2/qtsvg.html
QtXml 4.2.0 Qt 4.2.0 Reference http://doc.qt.digia.com
Manual /4.2/qtxml.html
The MIT Shared MIT-SHM - The MIT http://refspecs.linux-
Memory Extension Shared Memory foundation.org/X11/mi
Extension - X version t-shm.pdf
11, Release 5
4 © 2021 ISO/IEC – All rights reserved

Name Title URL
X Display Power X Display Power http://refspecs.linux-
Management Signaling Management Signaling foundation.org/X11/D
(DPMS) Extension -
PMSlib.pdf
Library Specificationi -
Version 1.0
X Extended Visual Extended Visual http://refspecs.linux-
Interface Extension Information Extension - foundation.org/X11/ev
Version 1.0 i.pdf
X Nonrectangular X Nonrectangular http://refspecs.linux-
Window Shape Window Shape foundation.org/X11/sh
Extension Library Extension Library - apelib.pdf
Version 1.0
X Record Extension X Record Extension http://refspecs.linux-
Library Library - Version 1.13 foundation.org/X11/re
cordlib.pdf
X Security Extension Security Extension http://refspecs.linux-
Specification - Version foundation.org/X11/se
Specification
7.1 curity.pdf
X Synchronization X Synchronization http://refspecs.linux-
Extension Library Extension Library - foundation.org/X11/sy
Version 3.0 nclib.pdf
X11 C Library Xlib - C Language X http://refspecs.linux-
Interface - X Version 11 foundation.org/X11/xli
Release 6.4 b.pdf
X11 Input Library X Input Device http://refspecs.linux-
Extension Library - X foundation.org/X11/Xi
Version 11, Release 6.4 nput.pdf
X11 Inter-Client Inter-Client Exchange http
...