Executable and Linkable Format
Encyclopedia
In computing
, the Executable and Linkable Format (ELF, formerly called Extensible Linking Format) is a common standard file format
for executable
s, object code
, shared libraries, and core dump
s. First published in the System V Application Binary Interface
specification, and later in the Tool Interface Standard, it was quickly accepted among different vendors of Unix
systems. In 1999 it was chosen as the standard binary file format for Unix and Unix-like
systems on x86 by the 86open project.
Unlike many proprietary executable file formats, ELF is very flexible and extensible, and it is not bound to any particular processor or architecture. This has allowed it to be adopted by many different operating system
s on many different platforms.
The ELF file format is also used as a generic object and executable format for binary images used with embedded processors like AVR
's.
Each ELF file is made up of one ELF header, followed by file data. The file data can include:
The segments contain information that is necessary for runtime execution of the file, while sections contain important data for linking and relocation. Any byte in the entire file can be owned by at most one section, and there can be orphan bytes which are not owned by any section.
It has replaced a.out and COFF
formats in Unix-like
operating systems:
ELF has also seen some adoption in non-Unix operating systems, such as:
Some game consoles also use ELF:
Other operating systems running on PowerPC
using ELF:
Some operating systems for mobile phones and mobile devices use ELF:
Some phones can run ELF files through the use of a patch
that adds assembly code
to the main firmware
(known as the ELFPack, in the underground modding
culture).
Also, Dolphin Emulator can open ELF files.
format for Unix
and Unix-like
operating system
s on the common PC compatible x86 architecture, so as to encourage software developers to port to the architecture. The initial idea was to standardize on a small subset of Spec 1170, a predecessor of the Single UNIX Specification
, and the GNU C Library (glibc) to enable unmodified binaries to run on the x86 UNIX-like operating systems. The project was originally referred to as "Spec 150".
The format eventually chosen was ELF, specifically the Linux implementation of ELF, after it had turned out to be a de facto standard
supported by all involved vendors and operating systems.
The group started email discussions in 1997 and first met in person at the Santa Cruz Operation offices on 1997-08-22.
The steering committee was Marc Ewing
, Dion Johnson, Evan Leibovitch, Bruce Perens
, Andrew Roach, Bryan Sparks and Linus Torvalds
. Other people on the project were Tim Bird, Keith Bostic
, Chuck Cranor, Michael Davidson, Chris G. Demetriou, Ulrich Drepper, Don Dugger, Steve Ginzburg, Jon "maddog" Hall, Ron Holt, Jordan Hubbard
, Dave Jensen, Kean Johnston, Andrew Josey, Robert Lipe, Bela Lubkin, Tim Marsland, Greg Page, Ronald Joe Record, Tim Ruckle, Joel Silverstein, Chia-pi Tien and Erik Troan. Operating systems and companies represented were BeOS
, BSDI, FreeBSD
, Intel, Linux
, NetBSD
, SCO and SunSoft, Inc..
The project progressed and in mid-1998, SCO began developing lxrun
, an open-source compatibility layer
capable of running Linux binaries on OpenServer, UnixWare
, and Solaris. SCO announced official support of lxrun at LinuxWorld
in March 1999. Sun Microsystems
began officially supporting lxrun
for Solaris in early 1999, and has since moved to integrated support of the Linux binary format via Solaris Containers for Linux Applications.
With the BSDs having long supported Linux binaries (through a compatibility layer
) and the main x86 Unix vendors having added support for the format, the project decided that Linux ELF was the format chosen by the industry and "declare[d] itself dissolved" on July 25, 1999.
capabilities. It is aimed for Linux
and other Unix-like
operations systems. Additionally to the CPU architecture abstraction (byte order, word size, CPU instruction set
etc.), there is the potential advantage of software-platform abstraction e.g. binaries which support multiple kernel ABIs
versions.
A proof-of-concept Ubuntu 9.04
image (VM image of Ubuntu 9.04 with Fat Binary support) and development tools are available. As of 2011, support for FatELF is not integrated in the kernel mainline.
Computing
Computing is usually defined as the activity of using and improving computer hardware and software. It is the computer-specific part of information technology...
, the Executable and Linkable Format (ELF, formerly called Extensible Linking Format) is a common standard file format
File format
A file format is a particular way that information is encoded for storage in a computer file.Since a disk drive, or indeed any computer storage, can store only bits, the computer must have some way of converting information to 0s and 1s and vice-versa. There are different kinds of formats for...
for executable
Executable
In computing, an executable file causes a computer "to perform indicated tasks according to encoded instructions," as opposed to a data file that must be parsed by a program to be meaningful. These instructions are traditionally machine code instructions for a physical CPU...
s, object code
Object code
Object code, or sometimes object module, is what a computer compiler produces. In a general sense object code is a sequence of statements in a computer language, usually a machine code language....
, shared libraries, and core dump
Core dump
In computing, a core dump consists of the recorded state of the working memory of a computer program at a specific time, generally when the program has terminated abnormally...
s. First published in the System V Application Binary Interface
Application binary interface
In computer software, an application binary interface describes the low-level interface between an application program and the operating system or another application.- Description :...
specification, and later in the Tool Interface Standard, it was quickly accepted among different vendors of Unix
Unix
Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
systems. In 1999 it was chosen as the standard binary file format for Unix and Unix-like
Unix-like
A Unix-like operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification....
systems on x86 by the 86open project.
Unlike many proprietary executable file formats, ELF is very flexible and extensible, and it is not bound to any particular processor or architecture. This has allowed it to be adopted by many different operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
s on many different platforms.
The ELF file format is also used as a generic object and executable format for binary images used with embedded processors like AVR
Atmel AVR
The AVR is a modified Harvard architecture 8-bit RISC single chip microcontroller which was developed by Atmel in 1996. The AVR was one of the first microcontroller families to use on-chip flash memory for program storage, as opposed to one-time programmable ROM, EPROM, or EEPROM used by other...
's.
ELF file layout
- Program header table, describing zero or more segments
- Section header table, describing zero or more sections
- Data referred to by entries in the program header table or section header table
The segments contain information that is necessary for runtime execution of the file, while sections contain important data for linking and relocation. Any byte in the entire file can be owned by at most one section, and there can be orphan bytes which are not owned by any section.
Tools
readelfis a Unix binary utility that displays information about one or more ELF files. An open-source implementation is provided by GNU Binutils.elfdumpis a command for viewing ELF information in an ELF file, available under Solaris and FreeBSDFreeBSDFreeBSD is a free Unix-like operating system descended from AT&T UNIX via BSD UNIX. Although for legal reasons FreeBSD cannot be called “UNIX”, as the direct descendant of BSD UNIX , FreeBSD’s internals and system APIs are UNIX-compliant...
.objdumpprovides a wide range of information about ELF files and other object formats.Objdumpobjdump is a program for displaying various information about object files. For instance, it can be used as a disassembler to view executable in assembly form...objdumpuses the Binary File Descriptor library as a back-end to structure the ELF data.- The Unix
fileutility can display some information about ELF files, including the instruction set architecture for which the code in a relocatable, executable, or shared object file is intended, or on which an ELF core dumpCore dumpIn computing, a core dump consists of the recorded state of the working memory of a computer program at a specific time, generally when the program has terminated abnormally...
was produced.
Applications
The ELF format has replaced older executable formats in various environments.It has replaced a.out and COFF
COFF
The Common Object File Format is a specification of a format for executable, object code, and shared library computer files used on Unix systems...
formats in Unix-like
Unix-like
A Unix-like operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification....
operating systems:
- LinuxLinuxLinux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
- Solaris
- IRIXIRIXIRIX is a computer operating system developed by Silicon Graphics, Inc. to run natively on their 32- and 64-bit MIPS architecture workstations and servers. It was based on UNIX System V with BSD extensions. IRIX was the first operating system to include the XFS file system.The last major version...
- FreeBSDFreeBSDFreeBSD is a free Unix-like operating system descended from AT&T UNIX via BSD UNIX. Although for legal reasons FreeBSD cannot be called “UNIX”, as the direct descendant of BSD UNIX , FreeBSD’s internals and system APIs are UNIX-compliant...
- NetBSDNetBSDNetBSD is a freely available open source version of the Berkeley Software Distribution Unix operating system. It was the second open source BSD descendant to be formally released, after 386BSD, and continues to be actively developed. The NetBSD project is primarily focused on high quality design,...
- OpenBSDOpenBSDOpenBSD is a Unix-like computer operating system descended from Berkeley Software Distribution , a Unix derivative developed at the University of California, Berkeley. It was forked from NetBSD by project leader Theo de Raadt in late 1995...
- DragonFly BSDDragonFly BSDDragonFly BSD is a free Unix-like operating system created as a fork of FreeBSD 4.8. Matthew Dillon, an Amiga developer in the late 1980s and early 1990s and a FreeBSD developer between 1994 and 2003, began work on DragonFly BSD in June 2003 and announced it on the FreeBSD mailing lists on July...
- Syllable
- HP-UXHP-UXHP-UX is Hewlett-Packard's proprietary implementation of the Unix operating system, based on UNIX System V and first released in 1984...
(except for 32-bit PA-RISC programs which continue to use SOMSystem Object Model (file format)In computing, the System Object Model is a proprietary executable file format developed by Hewlett-Packard for its HP-UX and MPE/ix operating systems....
) - BeOSBeOSBeOS is an operating system for personal computers which began development by Be Inc. in 1991. It was first written to run on BeBox hardware. BeOS was optimized for digital media work and was written to take advantage of modern hardware facilities such as symmetric multiprocessing by utilizing...
Revision 4 and later for x86 based computers (where it replaced the Portable ExecutablePortable ExecutableThe Portable Executable format is a file format for executables, object code and DLLs, used in 32-bit and 64-bit versions of Windows operating systems. The term "portable" refers to the format's versatility in numerous environments of operating system software architecture...
format; the PowerPCPowerPCPowerPC is a RISC architecture created by the 1991 Apple–IBM–Motorola alliance, known as AIM...
version stayed with Preferred Executable FormatPreferred Executable FormatThe Preferred Executable Format is a file format that specifies the format of executable files and other object code. PEF executables are also called Code Fragment Manager files ....
) - HaikuHaiku (operating system)Haiku is a free and open source operating system compatible with BeOS. Its development began in 2001, and the operating system became self-hosting in 2008, with the first alpha release in September 2009, the second in May 2010 and the third in June 2011....
ELF has also seen some adoption in non-Unix operating systems, such as:
- OpenVMSOpenVMSOpenVMS , previously known as VAX-11/VMS, VAX/VMS or VMS, is a computer server operating system that runs on VAX, Alpha and Itanium-based families of computers. Contrary to what its name suggests, OpenVMS is not open source software; however, the source listings are available for purchase...
, in its Itanium version
Some game consoles also use ELF:
- PlayStation PortablePlayStation PortableThe is a handheld game console manufactured and marketed by Sony Corporation Development of the console was announced during E3 2003, and it was unveiled on , 2004, at a Sony press conference before E3 2004...
, PlayStation 2PlayStation 2The PlayStation 2 is a sixth-generation video game console manufactured by Sony as part of the PlayStation series. Its development was announced in March 1999 and it was first released on March 4, 2000, in Japan...
, PlayStation 3PlayStation 3The is the third home video game console produced by Sony Computer Entertainment and the successor to the PlayStation 2 as part of the PlayStation series. The PlayStation 3 competes with Microsoft's Xbox 360 and Nintendo's Wii as part of the seventh generation of video game consoles... - WiiWiiThe Wii is a home video game console released by Nintendo on November 19, 2006. As a seventh-generation console, the Wii primarily competes with Microsoft's Xbox 360 and Sony's PlayStation 3. Nintendo states that its console targets a broader demographic than that of the two others...
- GP2XGP2XThe GP2X is an open-source, Linux-based handheld video game console and portable media player developed by South Korean company GamePark Holdings. It was released on November 10, 2005, in South Korea only....
. - Dreamcast
Other operating systems running on PowerPC
PowerPC
PowerPC is a RISC architecture created by the 1991 Apple–IBM–Motorola alliance, known as AIM...
using ELF:
- AmigaOS 4AmigaOS 4AmigaOS 4, , is a line of Amiga operating systems which runs on PowerPC microprocessors. It is mainly based on AmigaOS 3.1 source code, and partially on version 3.9 developed by Haage & Partner...
, the ELF executable has replaced the previous EHF (Extended Hunk Format) which was used on Amigas equipped with PPC processor expansion cards. - MorphOSMorphOSMorphOS is an Amiga-compatible computer operating system. It is a mixed proprietary and open source OS produced for the Pegasos PowerPC processor based computer, PowerUP accelerator equipped Amiga computers, and a series of Freescale development boards that use the Genesi firmware, including the...
Some operating systems for mobile phones and mobile devices use ELF:
- Symbian OS v9 uses E32Image format that is based on the ELF file format;
- Sony EricssonSony EricssonSony Ericsson Mobile Communications AB is a joint venture established on October 1, 2001 by the Japanese consumer electronics company Sony Corporation and the Swedish telecommunications company Ericsson to manufacture mobile phones....
, for example, the W800iSony Ericsson W800The W800 Walkman, released in 2005 , was the first Sony Ericsson phone to use the Walkman brand. The phone features Bluetooth v1.2 , Infrared and USB connectivity....
, W610Sony Ericsson W610iThe Sony Ericsson W610i phone is based on the Sony Ericsson K550 and Sony Ericsson K610i. It is a quad-band GSM phone, but it does not offer 3G . The W610i has colour options similar to the Sony Ericsson W880i...
, W300, etc. - SiemensSiemensSiemens may refer toSiemens, a German family name carried by generations of telecommunications industrialists, including:* Werner von Siemens , inventor, founder of Siemens AG...
, the SGOLD and SGOLD2 platforms: from Siemens C65Siemens C65The Siemens C65 is a mobile phone announced by Siemens in March 2004. It weighs 86 g and its dimensions are 100 x 45 x 16 mm . Its display is a 130x130 pixels, 65K colors CSTN LCD....
to S75 and BenQ-Siemens E71/EL71BenQ-Siemens EL71The BenQ-Siemens EL71 is a slider-type GSM triband mobile phone. Its name came about because of BenQ's acquisition of Siemens' mobile communication division at the end of 2005; the Benq-Siemens brand is meant to be transitory, before all phones are produced under the BenQ brand.The phone supports...
); - MotorolaMotorolaMotorola, Inc. was an American multinational telecommunications company based in Schaumburg, Illinois, which was eventually divided into two independent public companies, Motorola Mobility and Motorola Solutions on January 4, 2011, after losing $4.3 billion from 2007 to 2009...
, for example, the E398, SLVR L7, v360, v3i (and all phone LTE2 which has the patch applied) - Bada (operating system)Bada (operating system)Bada is an operating system for mobile devices such as smartphones and tablet computers. It is developed by the Samsung Electronics. Its name is derived from " ", meaning "ocean" or "sea" in Korean...
, for example, the Samsung Wave S8500Samsung Wave S8500The Samsung Wave GT-S8500 is the first touchscreen smartphone running the new bada operating system designed by Samsung, which was commercially released on June 1, 2010...
.
Some phones can run ELF files through the use of a patch
Patch (computing)
A patch is a piece of software designed to fix problems with, or update a computer program or its supporting data. This includes fixing security vulnerabilities and other bugs, and improving the usability or performance...
that adds assembly code
Assembly language
An assembly language is a low-level programming language for computers, microprocessors, microcontrollers, and other programmable devices. It implements a symbolic representation of the machine codes and other constants needed to program a given CPU architecture...
to the main firmware
Firmware
In electronic systems and computing, firmware is a term often used to denote the fixed, usually rather small, programs and/or data structures that internally control various electronic devices...
(known as the ELFPack, in the underground modding
Modding
Modding is a slang expression that is derived from the verb "modify". Modding refers to the act of modifying a piece of hardware or software or anything else for that matter, to perform a function not originally conceived or intended by the designer...
culture).
Also, Dolphin Emulator can open ELF files.
Specifications
- Generic:
- System V Application Binary Interface Edition 4.1 (1997-03-18)
- System V ABI Update (October 2009)
- ELF-64 Object File Format Version 1.5 Draft 2 (May 1998)
- AMD64:
- ARMARM architectureARM is a 32-bit reduced instruction set computer instruction set architecture developed by ARM Holdings. It was named the Advanced RISC Machine, and before that, the Acorn RISC Machine. The ARM architecture is the most widely used 32-bit ISA in numbers produced...
: - IA-32IA-32IA-32 , also known as x86-32, i386 or x86, is the CISC instruction-set architecture of Intel's most commercially successful microprocessors, and was first implemented in the Intel 80386 as a 32-bit extension of x86 architecture...
: - IA-64:
- Itanium Software Conventions and Runtime Guide (September 2000)
- M32RM32RThe M32R is a 32-bit RISC instruction set architecture developed by Mitsubishi for embedded microprocessors and microcontrollers. The ISA is now owned by Renesas Electronics Corporation, and the company designs and fabricates M32R implementations. M32R processors are used in embedded systems such...
:- M32R ELF ABI Supplement Version 1.2 (2004-08-26)
- MIPSMIPS architectureMIPS is a reduced instruction set computer instruction set architecture developed by MIPS Technologies . The early MIPS architectures were 32-bit, and later versions were 64-bit...
: - Motorola 6800Motorola 6800The 6800 was an 8-bit microprocessor designed and first manufactured by Motorola in 1974. The MC6800 microprocessor was part of the M6800 Microcomputer System that also included serial and parallel interface ICs, RAM, ROM and other support chips...
: - PA-RISCPA-RISCPA-RISC is an instruction set architecture developed by Hewlett-Packard. As the name implies, it is a reduced instruction set computer architecture, where the PA stands for Precision Architecture...
:- ELF Supplement for PA-RISC Version 1.43 (October 6, 1997)
- PowerPCPowerPCPowerPC is a RISC architecture created by the 1991 Apple–IBM–Motorola alliance, known as AIM...
:- System V ABI, PPC Supplement
- PowerPC Embedded Application Binary Interface 32-Bit Implementation (1995-10-01)
- 64-bit PowerPC ELF Application Binary Interface Supplement Version 1.9 (2004)
- SPARCSPARCSPARC is a RISC instruction set architecture developed by Sun Microsystems and introduced in mid-1987....
: - S/390:
- zSeriesZSeriesIBM System z, or earlier IBM eServer zSeries, is a brand name designated by IBM to all its mainframe computers.In 2000, IBM rebranded the existing System/390 to IBM eServer zSeries with the e depicted in IBM's red trademarked symbol, but because no specific machine names were changed for...
: - Symbian OS 9:
86open
86open was a project to form consensus on a common binary fileBinary file
A binary file is a computer file which may contain any type of data, encoded in binary form for computer storage and processing purposes; for example, computer document files containing formatted text...
format for Unix
Unix
Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
and Unix-like
Unix-like
A Unix-like operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification....
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
s on the common PC compatible x86 architecture, so as to encourage software developers to port to the architecture. The initial idea was to standardize on a small subset of Spec 1170, a predecessor of the Single UNIX Specification
Single UNIX Specification
The Single UNIX Specification is the collective name of a family of standards for computer operating systems to qualify for the name "Unix"...
, and the GNU C Library (glibc) to enable unmodified binaries to run on the x86 UNIX-like operating systems. The project was originally referred to as "Spec 150".
The format eventually chosen was ELF, specifically the Linux implementation of ELF, after it had turned out to be a de facto standard
De facto standard
A de facto standard is a custom, convention, product, or system that has achieved a dominant position by public acceptance or market forces...
supported by all involved vendors and operating systems.
The group started email discussions in 1997 and first met in person at the Santa Cruz Operation offices on 1997-08-22.
The steering committee was Marc Ewing
Marc Ewing
Marc Ewing is the creator and originator of the Red Hat brand of software, most notably the Red Hat range of Linux operating system distributions. He was involved in the 86open project in the mid-90s....
, Dion Johnson, Evan Leibovitch, Bruce Perens
Bruce Perens
Bruce Perens is a computer programmer and advocate in the open source community. He created the Open Source Definition and published the first formal announcement and manifesto of open source. He co-founded the Open Source Initiative with Eric S...
, Andrew Roach, Bryan Sparks and Linus Torvalds
Linus Torvalds
Linus Benedict Torvalds is a Finnish software engineer and hacker, best known for having initiated the development of the open source Linux kernel. He later became the chief architect of the Linux kernel, and now acts as the project's coordinator...
. Other people on the project were Tim Bird, Keith Bostic
Keith Bostic
Keith Bostic is a computer programmer from the United States.In 1986, Bostic joined the Computer Systems Research Group at the University of California, Berkeley. He was one of the principal architects of the Berkeley 4.4BSD and 4.4BSD-Lite releases...
, Chuck Cranor, Michael Davidson, Chris G. Demetriou, Ulrich Drepper, Don Dugger, Steve Ginzburg, Jon "maddog" Hall, Ron Holt, Jordan Hubbard
Jordan Hubbard
Jordan K. Hubbard is a long-time open source developer, authoring software like the Ardent Window Manager and various other open source tools and libraries before finally co-founding the FreeBSD project. He started the FreeBSD project in 1993 with Nate Williams and Rodney W. Grimes, also creating...
, Dave Jensen, Kean Johnston, Andrew Josey, Robert Lipe, Bela Lubkin, Tim Marsland, Greg Page, Ronald Joe Record, Tim Ruckle, Joel Silverstein, Chia-pi Tien and Erik Troan. Operating systems and companies represented were BeOS
BeOS
BeOS is an operating system for personal computers which began development by Be Inc. in 1991. It was first written to run on BeBox hardware. BeOS was optimized for digital media work and was written to take advantage of modern hardware facilities such as symmetric multiprocessing by utilizing...
, BSDI, FreeBSD
FreeBSD
FreeBSD is a free Unix-like operating system descended from AT&T UNIX via BSD UNIX. Although for legal reasons FreeBSD cannot be called “UNIX”, as the direct descendant of BSD UNIX , FreeBSD’s internals and system APIs are UNIX-compliant...
, Intel, Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
, NetBSD
NetBSD
NetBSD is a freely available open source version of the Berkeley Software Distribution Unix operating system. It was the second open source BSD descendant to be formally released, after 386BSD, and continues to be actively developed. The NetBSD project is primarily focused on high quality design,...
, SCO and SunSoft, Inc..
The project progressed and in mid-1998, SCO began developing lxrun
Lxrun
In Unix computing, lxrun is a compatibility layer to allow Linux binaries to run on UnixWare, SCO OpenServer and Solaris without recompilation. It was created by Mike Davidson. It has been an open source software project since 1997, and is available under the Mozilla Public License...
, an open-source compatibility layer
Compatibility layer
A compatibility layer is a term that refers to components that allow for non-native support of components.In software engineering, a compatibility layer allows binaries for a legacy or foreign system to run on a host system. This translates system calls for the foreign system into native system...
capable of running Linux binaries on OpenServer, UnixWare
UnixWare
UnixWare is a Unix operating system maintained by The SCO Group . UnixWare is typically deployed as a server rather than desktop. Binary distributions of UnixWare are available for x86 architecture computers. It was originally released by Univel, a jointly owned venture of AT&T's Unix System...
, and Solaris. SCO announced official support of lxrun at LinuxWorld
LinuxWorld
LinuxWorld has various meanings:* LinuxWorld Conference and Expo - a series of Linux conferences worldwide that became OpenSource World in 2009.* LinuxWorld Magazine - a print publication produced from 2003 to 2006...
in March 1999. Sun Microsystems
Sun Microsystems
Sun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...
began officially supporting lxrun
Lxrun
In Unix computing, lxrun is a compatibility layer to allow Linux binaries to run on UnixWare, SCO OpenServer and Solaris without recompilation. It was created by Mike Davidson. It has been an open source software project since 1997, and is available under the Mozilla Public License...
for Solaris in early 1999, and has since moved to integrated support of the Linux binary format via Solaris Containers for Linux Applications.
With the BSDs having long supported Linux binaries (through a compatibility layer
Compatibility layer
A compatibility layer is a term that refers to components that allow for non-native support of components.In software engineering, a compatibility layer allows binaries for a legacy or foreign system to run on a host system. This translates system calls for the foreign system into native system...
) and the main x86 Unix vendors having added support for the format, the project decided that Linux ELF was the format chosen by the industry and "declare[d] itself dissolved" on July 25, 1999.
FatELF: Universal Binaries for Linux
FatELF is an ELF binary-format extension which adds Fat binaryFat binary
A fat binary is a computer program with code native to multiple Instruction sets which can consequently be run on multiple processor types. The usual method of implementation is to include a version of the machine code for each instruction set, preceded by code compatible with all operating...
capabilities. It is aimed for Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
and other Unix-like
Unix-like
A Unix-like operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification....
operations systems. Additionally to the CPU architecture abstraction (byte order, word size, CPU instruction set
Instruction set
An instruction set, or instruction set architecture , is the part of the computer architecture related to programming, including the native data types, instructions, registers, addressing modes, memory architecture, interrupt and exception handling, and external I/O...
etc.), there is the potential advantage of software-platform abstraction e.g. binaries which support multiple kernel ABIs
Application binary interface
In computer software, an application binary interface describes the low-level interface between an application program and the operating system or another application.- Description :...
versions.
A proof-of-concept Ubuntu 9.04
Ubuntu (operating system)
Ubuntu is a computer operating system based on the Debian Linux distribution and distributed as free and open source software. It is named after the Southern African philosophy of Ubuntu...
image (VM image of Ubuntu 9.04 with Fat Binary support) and development tools are available. As of 2011, support for FatELF is not integrated in the kernel mainline.
See also
- Comparison of executable file formatsComparison of executable file formatsThis is a comparison of executable file formats.Among the above formats, the ones in most common use are PE , ELF and Mach-O .- References :...
- Portable ExecutablePortable ExecutableThe Portable Executable format is a file format for executables, object code and DLLs, used in 32-bit and 64-bit versions of Windows operating systems. The term "portable" refers to the format's versatility in numerous environments of operating system software architecture...
- DWARFDWARFDWARF is a widely used, standardized debugging data format. DWARF was originally designed along with Executable and Linkable Format , although it is independent of object file formats...
- Debug With Attributed Record Format - Application binary interfaceApplication binary interfaceIn computer software, an application binary interface describes the low-level interface between an application program and the operating system or another application.- Description :...
- VDSOVDSOVDSOs are a way to export kernel space routines to user space applications, using standard mechanisms for linking and loading VDSOs (Virtual Dynamically-linked Shared Objects) are a way to export kernel space routines to user space applications, using standard mechanisms for linking and loading...
- Virtual DSO
Further reading
- An unsung hero: The hardworking ELF by Peter Seebach (2005-12-20)
- LibElf and GElf — A Library to Manipulate ELF Files by Neelakanth Nadgir (August 2001)
- The ELF Object File Format by Dissection by Eric Youngdale (1995-05-01)
- A Whirlwind Tutorial on Creating Really Teensy ELF Executables for Linux by Brian Raiter
- ELF relocation into non-relocatable objects by Julien Vanegue (2003-08-13)
- Embedded ELF debugging without ptrace by the ELFsh team (2005-08-01)
- Study of ELF loading and relocs by Pat Beirne (1999-08-03)
External links
- FreeBSD Handbook: Binary formats
- FreeBSD elf(5) manual page
- NetBSD ELF FAQ
- Solaris's Linker and Libraries Guide ©2001 Sun Microsystems
- The ERESI project : reverse engineering on ELF-based operating systems
- Linux Today article on 86open July 26, 1999
- Announcement of 86open on Debian Announce mailing list October 10, 1997, Bruce PerensBruce PerensBruce Perens is a computer programmer and advocate in the open source community. He created the Open Source Definition and published the first formal announcement and manifesto of open source. He co-founded the Open Source Initiative with Eric S...
- Declaration of Ulrich Drepper (PDF) in The SCO Group vs IBMIBMInternational Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
, September 19, 2006 - http://computerorganizationby-delrosario.blogspot.com/ Check this out ttp://computerorganizationby-delrosario.blogspot.com/],Structured Computer Organization