LSB Common 5.0 Edition
Copyright © 2015 Linux Foundation
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
Portions of the text may be copyrighted by the following parties:
The Regents of the University of California
Free Software Foundation
Ian F. Darwin
BSDI (now Wind River)
Jean-loup Gailly and Mark Adler
Massachusetts Institute of Technology
Easy Software Products
Python Software Foundation
These excerpts are being used in accordance with their respective licenses.
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PowerPC is a registered trademark and PowerPC Architecture is a trademark of the IBM Corporation.
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PAM documentation is Copyright (C) Andrew G. Morgan 1996-9. All rights reserved. Used under the following conditions:
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Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
The name of the author may not be used to endorse or promote products derived from this software without specific prior written permission.
This release is dedicated to the memory of Christopher Yeoh, a long-time friend and colleague, and a contributor to LSB from the earliest days. Without his dedication this work would not have been possible.
This is version 5.0 of the Linux Standard Base Common Definitions. This specification is one of a series of volumes under the collective title Linux Standard Base:
Note that the Core and Desktop volumes consist of a generic volume augmented by an architecture-specific volume.
This is a released specification, version 5.0. Other documents may supersede or augment this specification.
A list of current released Linux Standard Base (LSB) specifications is available at http://refspecs.linuxbase.org.
If you wish to make comments regarding this document in a manner that is tracked by the LSB project, please submit them using our public bug database at http://bugs.linuxbase.org. Please enter your feedback, carefully indicating the title of the section for which you are submitting feedback, and the volume and version of the specification where you found the problem, quoting the incorrect text if appropriate. If you are suggesting a new feature, please indicate what the problem you are trying to solve is. That is more important than the solution, in fact.
If you do not have or wish to create a bug database account then you
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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:
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.
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.
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.
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.
The LSB specification set is divided into modules, each of which provides fundamental system interfaces, libraries, and runtime environment upon which all conforming applications and libraries using that module depend.
The modules of the Linux Standard Base are:
LSB Core - core components
LSB Desktop - desktop related components
LSB Languages - runtime languages
LSB Imaging - printing and scanning
LSB Trial Use - components that are not yet mandatory
Interfaces described in the LSB Core module specification are supplemented by other LSB module specifications. All other modules depend on the presence of LSB Core.
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. 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 of an LSB module specification may also contain additional information that is not referenced in the common part.
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.
The libraries listed in the following tables shall be available on a Linux Standard Base system, with the specified runtime names. The libraries listed in Table 2-2 are architecture specific, but shall be available on all LSB conforming systems under a name specified in each Architecture Specific Part of the LSB Core module.
Table 2-1. LSB Core Module Library Names
Table 2-2. LSB Core Module Library Names which vary by architecture
|libc||See architecture specific part.|
|libm||See architecture specific part.|
|proginterp||See architecture specific part.|
Table 2-3. LSB Desktop Module Library Names
Table 2-4. LSB Imaging Module Library Names
The commands listed in the following tables shall be available on a Linux Standard Base system, with the specified runtime names.
Table 2-6. LSB Core Module Command Names
Table 2-7. LSB Desktop Module Command Names
A conforming implementation is necessarily architecture specific, and must provide the interfaces specified by both the generic LSB specifications and the applicable architecture specific part.
Rationale: An implementation must provide at least the interfaces specified in these specifications. It may also provide additional interfaces.
A conforming implementation shall satisfy the following requirements:
A processor architecture represents a family of related processors which may not have identical feature sets. The architecture specific part of the LSB Core Specification for a given target processor architecture describes a minimum acceptable processor. The implementation shall provide all features of this processor, whether in hardware or through emulation transparent to the application.
The implementation shall be capable of executing compiled applications having the format and using the system interfaces described in this specification.
The implementation shall provide libraries containing the interfaces specified by this specification, and shall provide a dynamic linking mechanism that allows these interfaces to be attached to applications at runtime. All the interfaces shall behave as specified in this specification.
The map of virtual memory provided by the implementation shall conform to the requirements of this specification.
The implementation's low-level behavior with respect to function call linkage, system traps, signals, and other such activities shall conform to the formats described in this specification.
The implementation shall provide all of the mandatory interfaces in their entirety.
The implementation may provide one or more of the optional interfaces. Each optional interface that is provided shall be provided in its entirety. The product documentation shall state which optional interfaces are provided.
The implementation shall provide all files and utilities specified as part of this specification in the format defined here and in other documents normatively included by reference. All commands and utilities shall behave as required by this specification. The implementation shall also provide all mandatory components of an application's runtime environment that are included or referenced in this specification.
The implementation, when provided with standard data formats and values at a named interface, shall provide the behavior defined for those values and data formats at that interface. However, a conforming implementation may consist of components which are separately packaged and/or sold. For example, a vendor of a conforming implementation might sell the hardware, operating system, and windowing system as separately packaged items.
The implementation may provide additional interfaces with different names. It may also provide additional behavior corresponding to data values outside the standard ranges, for standard named interfaces.
The implementation shall report whether supports for each of the modules constituting this specification is currently available, with the exception of the Trial Use module, which need not be reported. At a minimum, this reporting shall be performed using the lsb_release command described in the LSB Core module specification.
Rationale: An implementation must support all modules described as mandatory in this specification. However, excepting the LSB Core module, which is always required, the support for a module may not be installed or enabled. The intent of this clause is to indicate a run-time query mechanism to determine the status of module support.
A conforming application containing object files is necessarily architecture specific, and must conform to both the generic LSB Core module specification (LSB Core - Generic) and the relevant architecture specific part of the LSB Core Specification. A conforming application which contains no object files may be architecture neutral. Architecture neutral applications shall conform only to the requirements of the generic LSB Core module specification (LSB Core - Generic).
In addition, the application may optionally conform to one or more additional LSB module specifications.
A conforming application shall satisfy the following requirements:
Executable files shall be either object files in the format defined in the Object Format section of this specification, or script files in a scripting language where the interpreter is required by this specification.
Object files shall participate in dynamic linking as defined in the Program Loading and Linking section of this specification.
Object files shall employ only the instructions, traps, and other low-level facilities defined as being for use by applications in the Low-Level System Information section of this specification
If the application requires any optional interface defined in this specification in order to be installed or to execute successfully, the requirement for that optional interface shall be stated in the application's documentation.
The application shall not use any interface or data format that is not required to be provided by a conforming implementation, unless such an interface or data format is supplied by another application through direct invocation of that application during execution. The other application must also be a conforming application, and the use of such interface or data format, as well as its source (in other words, the other conforming application), shall be identified in the documentation of the application.
The application shall not use any values for a named interface that are reserved for vendor extensions.
A strictly conforming application shall not require or use any interface, facility, or implementation-defined extension not defined in this specification in order to be installed or to execute successfully.
Applications distributed using the packaging specification described in the generic LSB Core specification (LSB Core - Generic) may, in addition to other package dependencies described in this specification, declare a dependency on "lsb" with a version of 5.0.
Implementation Note: Application dependencies should generally be as limited as possible. For example, if a 64-bit POWER application only depends on items from the core specification, a dependency on "lsb-core-ppc64" may be more appropriate than a dependency on "lsb". The latter dependency could cause an implementation to install a number of other modules that may not be necessary to execute this application.
For the purposes of this document, the terms given in ISO/IEC Directives, Part 2, Annex H and the following apply.
Some LSB specification documents have both a generic, architecture-neutral part and an architecture-specific part. The latter describes elements whose definitions may be unique to a particular processor architecture. The term archLSB may be used in the generic part to refer to the corresponding section of the architecture-specific part.
The total set of interfaces that are available to be used in the compiled binary code of a conforming application, including the run-time details such as calling conventions, binary format, C++ name mangling, etc.
Describes a value or behavior that is not defined by this document but is selected by an implementor. The value or behavior may vary among implementations that conform to this document. An application should not rely on the existence of the value or behavior. An application that relies on such a value or behavior cannot be assured to be portable across conforming implementations. The implementor shall document such a value or behavior so that it can be used correctly by an application.
A file that is read by an interpreter (e.g., awk). The first line of the shell script includes a reference to its interpreter binary.
The total set of interfaces that are available to be used in the source code of a conforming application. Due to translations, the Binary Standard and the Source Standard may contain some different interfaces.
Describes the nature of a value or behavior not defined by this document which results from use of an invalid program construct or invalid data input. The value or behavior may vary among implementations that conform to this document. An application should not rely on the existence or validity of the value or behavior. An application that relies on any particular value or behavior cannot be assured to be portable across conforming implementations.
Describes the nature of a value or behavior not specified by this document which results from use of a valid program construct or valid data input. The value or behavior may vary among implementations that conform to this document. An application should not rely on the existence or validity of the value or behavior. An application that relies on any particular value or behavior cannot be assured to be portable across conforming implementations.
In addition, for the portions of this specification which build on IEEE Std 1003.1-2001, the definitions given in IEEE Std 1003.1-2001, Base Definitions, Chapter 3 apply.
Throughout this document, the following typographic conventions are used:
the name of a function
the name of a command or utility
a constant value
Throughout this specification, several tables of interfaces are presented. Each entry in these tables has the following format:
the name of the interface
An optional symbol version identifier, if required.
A reference number indexing the table of referenced specifications that follows this table.
GLIBC_2.0that is defined in the reference indicated by the tag SUSv4.
Note: For symbols with versions which differ between architectures, the symbol versions are defined in the architecture specific parts of of this module specification only. In the generic part, they will appear without symbol versions.
The LSB Core module of the LSB includes many interfaces described in the POSIX specification. For more details on this relationship, please see the LSB Core Generic volume.
The LSB Specification Authority is responsible for deciding the meaning of conformance to normative referenced standards in the LSB context. Problem reports regarding underlying or referenced standards in any other context will be referred to the relevant maintenance body for that standard.
The LSB is foundation of several other specification projects under the umbrella of the Linux Foundation (LF), which build on the interfaces defined here. However, beyond those specifications listed as Normative References in the various LSB specification volumes, this specification has no dependencies on other LF projects.
This specification is published under the terms of the GNU Free Documentation License, Version 1.1, March 2000
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