In computing, the Executable and Linkable Format ( ELF, formerly called Extensible Linking Format ) is a common standard file format for executables, object code, shared libraries, and core dumps.

Unlike many proprietary executable file formats, ELF is flexible and extensible, and it is not bound to any particular processor or architecture.

An ELF file has two views: The program header shows the segments used at run-time, whereas the section header lists the set of sections of the binary.

Each ELF file is made up of one ELF header, followed by file data.

* is a command for viewing ELF information in an ELF file, available under Solaris and FreeBSD.

* The Unix utility 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 dump was produced.

* Symbian OS v9 uses E32Image format that is based on the ELF file format ;

A few segment names of a typical ELF executable file are listed below.

The command can provide further details of the ELF file.

Consider an ELF executable file of size 10K.

After decompressing, two files are created: an ELF binary file called < tt > devnull </ tt > and a source script file called < tt > sslx. c </ tt >.

There are many different object file formats ; originally each type of computer had its own unique format, but with the advent of Unix and other portable operating systems, some formats, such as COFF and ELF have been defined and used on different kinds of systems.

DWARF was originally designed along with Executable and Linkable Format ( ELF ), although it is independent of object file formats.

These markings exist in the ELF header, and thus are both filesystem independent and part of the file object itself.

BusyBox benefits from the single binary approach, as it reduces the overheads introduced by the executable file format ( typically ELF ), and it allows code to be shared between multiple applications without requiring a library.

The CELF ( Compressed ELF ) files use a patented technique to compress the op codes within the executable and reduce the overall footprint of each executable file.

It has support for Zip, RAR, Tar, Gzip, Bzip2, OLE2, Cabinet, CHM, BinHex, SIS formats, most mail file formats, ELF executables and Portable Executable ( PE ) files compressed with UPX, FSG, Petite, NsPack, wwpack32, MEW, Upack and obfuscated with SUE, Y0da Cryptor.

While both Delphi and Kylix run on 32-bit Intel processors, Linux uses different register conventions than Windows and, of course, the executable and library file formats are different ; see DLL, EXE, ELF for details.

The ELF format has replaced older executable formats in various environments.

All versions of FASM can directly output any of the following: flat " raw " binary ( usable also as DOS COM executable or SYS driver ), objects: Executable and Linkable Format ( ELF ) or Common Object File Format ( COFF ) ( classic or MS-specific ), or executables in either MZ, ELF, or Portable Executable ( PE ) format ( including WDM drivers, allows custom MZ DOS stub ).

It was introduced in Unix System V, replaced the previously used a. out format, and formed the basis for extended specifications such as XCOFF and ECOFF, before being largely replaced by ELF, introduced with SVR4.

GNU Hurd, which uses GNU Mach as its microkernel, uses ELF, and not Mach-O, as its standard binary format.

The BeOS uses ELF format executable files, much as many other operating systems.

BeIA uses an extended version of ELF, the name of which is unknown but which has come to be known as CELF, from the CEL magic word within the executable header and the fact that it is derived from ELF format executables through a compression process.

AWStats supports most major web server log file formats including Apache ( NCSA combined / XLF / ELF log format or common / CLF log format ), WebStar, IIS ( W3C log format ) and many other common web server log formats.

The ELF executable format and SO shared library format used by most Unix-like systems allows to define several types of relocations.

They postulated that extremely low frequency ( ELF ) propagation might be involved, since Faraday cage screening is less effective in the ELF range.

* is a Unix binary utility that displays information about one or more ELF files.

Extremely low frequency ( ELF ) is a term used to describe radiation frequencies from 3 to 30 Hz.

NASM can output several binary formats including COFF, Portable Executable, a. out, ELF and Mach-O, though position-independent code is only supported for ELF object files.

In 2005 the FBI announced that the ELF, is America's greatest domestic terrorist threat, responsible for over 1, 200 " criminal incidents " amounting to tens of millions of dollars in damage to property, with the United States Department of Homeland Security confirming this regarding the ALF and ELF.

VLF is used to communicate with submarines near the surface ( for example using the transmitter DHO38 ), while ELF is used for deeply-submerged vessels.

At extra low frequencies ( ELF ) and very low frequencies the wavelength is very much larger than the separation between the earth's surface and the D layer of the ionosphere, so electromagnetic waves may propagate in this region as a waveguide.

At medium frequencies this appears to " bend " or reflect the signal around the horizon ; at lower frequencies ( VLF / ELF ) the accepted model is that of a ducted waveguide, in which the lower boundary is the earth's solid or liquid surface, and the upper boundary is the time-varying, spatially-varying, density-varying ionosphere.

ELF has also seen some adoption in non-Unix operating systems, such as:

Some game consoles also use ELF:

Movements such as the Earth Liberation Front ( ELF ) and Earth Liberation Army ( ELA ) also take this form of action, although focus on economic sabotage, rather than civil disobedience.

Marie also pleaded guilty to conspiring to carry out ELF actions and admitted involvement in 12 other ELF actions.

The World Health Organization ( WHO ) have used ELF to refer to the concept of " extremely low frequency ( ELF ) electric and magnetic fields ( EMF )" and have also referred to " ELF electric and magnetic fields in the frequency range > 0 to 100, 000 Hz ( 100 kHz ).

It also can be used as a debugger for Windows PE, Mac OS X, Mach-O, and Linux ELF executables.

As before, Open Firmware could also run a binary boot loader, and version 3. 0 added support for ELF objects as well as the XCOFF files versions 1. 0. 5 and 2. 0 supported.

Electromagnetic waves in the ELF frequency range ( 3 – 300 Hz ) ( see also SLF ) can penetrate seawater to depths of hundreds of meters, allowing communication with submarines at their operating depths.

Their U-20 team also played in the 2006 ELF Cup, finishing fourth of eight, winning one game ( 1-0 against Kyrgyzstan's national futsal team ) and drawing twice ( against Gagauzia and Greenland ) before losing 5-0 to Northern Cyprus in the semifinal.

Environmental Life Force ( ELF ), also known as the Original ELF, was the first radical environmental group in 1977 to use explosive and incendiary devices in defense of the environment.