XCOFF
Encyclopedia
XCOFF, for "eXtended COFF", is an improved and expanded version of the COFF
object file format defined by IBM
and used in AIX
. Early versions of the PowerPC
Macintosh also supported XCOFF, as did BeOS
.
XCOFF additions include the use of csects to provide subsection granularity of cross-references, and the use of stabs
for debugging
. Information for the handling of shared libraries is also more elaborate than for plain COFF.
More recently, IBM defined an XCOFF64 version supporting 64-bit
AIX, and used XCOFF32 to mean the original file format.
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...
object file format defined by IBM
IBM
International 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...
and used in AIX
AIX operating system
AIX AIX AIX (Advanced Interactive eXecutive, pronounced "a i ex" is a series of proprietary Unix operating systems developed and sold by IBM for several of its computer platforms...
. Early versions of the PowerPC
PowerPC
PowerPC is a RISC architecture created by the 1991 Apple–IBM–Motorola alliance, known as AIM...
Macintosh also supported XCOFF, as did 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...
.
XCOFF additions include the use of csects to provide subsection granularity of cross-references, and the use of stabs
Stabs
stabs is a debugging data format for storing information about computer programs for use by symbolic and source-level debuggers...
for debugging
Debugging
Debugging is a methodical process of finding and reducing the number of bugs, or defects, in a computer program or a piece of electronic hardware, thus making it behave as expected. Debugging tends to be harder when various subsystems are tightly coupled, as changes in one may cause bugs to emerge...
. Information for the handling of shared libraries is also more elaborate than for plain COFF.
More recently, IBM defined an XCOFF64 version supporting 64-bit
64-bit
64-bit is a word size that defines certain classes of computer architecture, buses, memory and CPUs, and by extension the software that runs on them. 64-bit CPUs have existed in supercomputers since the 1970s and in RISC-based workstations and servers since the early 1990s...
AIX, and used XCOFF32 to mean the original file format.