25:
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When compiled with appropriate options, a COFF object file will contain line number information for each possible break point in the text section of the object file. Line number information takes two forms: in the first, for each possible break point in the code, the line number table entry records
488:
Storage classes describe the type entity the symbol represents, and may include external variables (C_EXT), automatic (stack) variables (C_AUTO), register variables (C_REG), functions (C_FCN), and many others. The symbol type describes the interpretation of the symbol entity's value and includes
532:
of an object from the file once it is loaded into memory, minus the base address of the file image. If the file were to be mapped literally from disk to memory, the RVA would be the same as that of the offset into the file, but this is actually quite unusual.
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Note that COFF was not capable of representing line numbers or debugging symbols for included source as with header files rendering the COFF debugging information virtually useless without incompatible extensions.
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the address and its matching line number. In the second form, the entry identifies a symbol table entry representing the start of a function, enabling a breakpoint to be set using the function's name.
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However, the COFF design was both too limited and incompletely specified: there was a limit on the maximum number of sections, a limit on the length of section names, included source files, and the
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entry includes a name, storage class, type, value and section number. Short names (8 characters or fewer) are stored directly in the symbol table; longer names are stored as an
761:
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388:, or new processors. All real world implementations of COFF were necessarily violations of the standard as a result. This led to numerous COFF extensions.
585:
536:
Note that the RVA term is only used with objects in the image file. Once loaded into memory, the image base address is added, and ordinary VAs are used.
544:
The COFF file header stores the date and time that the object file was created as a 32-bit binary integer, representing the number of seconds since the
458:
was the introduction of multiple named sections in the object file. Different object files could have different numbers and types of sections.
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552:. Dates occurring after 19 January 2038 cannot be stored in this format, resulting in an instance of the
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470:) names for program functions and variables, and line number information, used for setting breakpoints and
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While extended versions of COFF continue to be used for some Unix and Unix-like platforms, primarily in
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ports and tool chains targeting embedded development each created their own, incompatible, variations.
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format included arbitrary sections, explicit processor declarations, and explicit address linkage.
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When a COFF file is generated, it is not usually known where in memory it will be loaded. The
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Relative virtual addresses (RVAs) are not to be confused with standard virtual addresses. A
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information was incapable of supporting real world languages such as
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format, and formed the basis for extended specifications such as
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where the first byte of the file will be loaded is called image
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An In-Depth Look into the Win32 Portable
Executable File Format
466:
The COFF symbolic debugging information consists of symbolic (
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18:
446:, and as a component of the PE header for executable files.
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UNIX System V/386 Release 3.2 Programmer's Guide, Volume II
477:
Symbolic names are stored in the COFF symbol table. Each
348:, different solutions to these and other issues emerged.
586:"LIB Reference (Embedded Visual C++ Programmers Guide)"
324:
environments and in some embedded development systems.
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With the release of SVR4, AT&T replaced COFF with
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into the string table at the end of the COFF object.
308:. COFF and its variants continue to be used on some
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49:. Unsourced material may be challenged and removed.
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8:
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729:"A Brief History of TI Object File Formats"
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772:
369:. Improvements over the existing AT&T
344:systems continued both inside and outside
155:application/x-coff, application/x-coffexec
548:, 1 January 1970 00:00:00
109:Learn how and when to remove this message
713:(Revision 4.1 ed.), archived from
646:"11 Common Object File Format (COFF)".
615:"IMAGE_FILE_HEADER structure (winnt.h)"
577:
120:
566:Comparison of executable file formats
332:The original Unix object file format
7:
47:adding citations to reliable sources
300:, before being largely replaced by
14:
384:, much less newer languages like
735:from the original on 2023-11-26.
710:Common Object File Format (COFF)
351:COFF was introduced in 1983, in
336:is unable to adequately support
23:
707:Microsoft Corporation (2006b),
288:, replaced the previously used
34:needs additional citations for
462:Symbolic debugging information
284:systems. It was introduced in
246:Executable and Linkable Format
1:
454:COFF's main improvement over
691:Understanding and Using COFF
741:"Common Object File Format"
693:, O'Reilly and Associates,
635:Microsoft Corporation 2006b
438:(PE) format. Developed for
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814:
689:Gircys, Gintaras (1988),
255:Common Object File Format
526:relative virtual address
505:Relative virtual address
151:Internet media type
943:Executable file formats
766:PE format documentation
365:platforms such as the
16:Executable file format
917:Comparison of formats
202:AT&T Corporation
43:improve this article
489:values for all the
436:Portable Executable
318:Portable Executable
242:Portable Executable
123:
590:msdn.microsoft.com
378:symbolic debugging
304:, introduced with
128:Filename extension
930:
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748:Texas Instruments
554:year 2038 problem
314:Microsoft Windows
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198:Developed by
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592:. Archived from
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428:embedded systems
408:and others used
338:shared libraries
230:Extended to
224:shared libraries
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678:Further reading
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756:External links
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684:MIPS COFF Spec
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278:computer files
275:shared library
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208:Type of format
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717:on 2006-12-16
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666:0-13-944885-3
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657:Prentice-Hall
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596:on 2003-08-25
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356:UNIX System V
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286:Unix System V
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60: –
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54:Find sources:
48:
44:
38:
37:
32:This article
30:
26:
21:
20:
828:
768:at Microsoft
747:
719:, retrieved
715:the original
709:
690:
648:
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619:. Retrieved
617:. 2018-05-12
609:
598:. Retrieved
594:the original
589:
580:
543:
535:
525:
523:
518:
515:base address
508:
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493:data types.
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479:symbol table
476:
465:
455:
453:
444:object files
425:
418:
375:
370:
350:
331:
312:systems, on
258:
254:
252:
161:Magic number
105:
96:
86:
79:
72:
65:
53:
41:Please help
36:verification
33:
807:object file
474:execution.
271:object code
803:Executable
721:2007-06-02
621:2023-12-22
600:2021-02-04
572:References
546:Unix epoch
440:Windows NT
396:format in
353:AT&T's
267:executable
216:executable
99:March 2010
69:newspapers
432:Microsoft
392:used the
342:Unix-like
310:Unix-like
937:Category
733:Archived
659:. 1989.
560:See also
540:Problems
519:sections
450:Features
358:for non-
346:AT&T
280:used on
261:) is a
809:formats
528:is the
472:tracing
328:History
190:Itanium
83:scholar
884:OS/360
864:Mach-O
697:
663:
483:offset
468:string
363:32-bit
320:), in
273:, and
263:format
220:object
212:Binary
133:none,
85:
78:
71:
64:
58:"COFF"
56:
904:XCOFF
844:ECOFF
819:a.out
744:(PDF)
653:(PDF)
456:a.out
410:ECOFF
394:XCOFF
371:a.out
334:a.out
298:ECOFF
294:XCOFF
290:a.out
238:ECOFF
234:XCOFF
186:00 02
181:AMD64
177:64 86
168:4C 01
90:JSTOR
76:books
922:.exe
859:Hunk
854:GOFF
829:COFF
805:and
764:and
695:ISBN
661:ISBN
414:SysV
367:3B20
322:UEFI
306:SVR4
296:and
282:Unix
265:for
259:COFF
253:The
188:for
179:for
172:i386
170:for
143:.lib
139:.obj
122:COFF
62:news
894:PEF
879:OMF
849:ELF
839:COM
834:CMD
824:AIF
550:UTC
434:'s
421:ELF
406:SGI
402:DEC
398:AIX
390:IBM
386:C++
360:VAX
302:ELF
45:by
939::
889:PE
874:NE
869:MZ
746:.
731:.
655:.
588:.
556:.
521:.
423:.
404:,
400:;
269:,
244:,
240:,
236:,
222:,
218:,
214:,
141:,
137:,
135:.o
899:X
795:e
788:t
781:v
750:.
669:.
624:.
603:.
491:C
382:C
316:(
257:(
112:)
106:(
101:)
97:(
87:·
80:·
73:·
66:·
39:.
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