1 .\" $OpenBSD: elf.5,v 1.12 2003/10/27 20:23:58 jmc Exp $
2 .\"Copyright (c) 1999 Jeroen Ruigrok van der Werven
3 .\"All rights reserved.
5 .\" %%%LICENSE_START(PERMISSIVE_MISC)
6 .\"Redistribution and use in source and binary forms, with or without
7 .\"modification, are permitted provided that the following conditions
9 .\"1. Redistributions of source code must retain the above copyright
10 .\" notice, this list of conditions and the following disclaimer.
11 .\"2. Redistributions in binary form must reproduce the above copyright
12 .\" notice, this list of conditions and the following disclaimer in the
13 .\" documentation and/or other materials provided with the distribution.
15 .\"THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 .\"ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 .\"IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 .\"ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 .\"FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 .\"DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 .\"OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 .\"HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 .\"LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 .\"OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 .\" $FreeBSD: src/share/man/man5/elf.5,v 1.21 2001/10/01 16:09:23 ru Exp $
30 .\" Slightly adapted - aeb, 2004-01-01
31 .\" 2005-07-15, Mike Frysinger <vapier@gentoo.org>, various fixes
32 .\" 2007-10-11, Mike Frysinger <vapier@gentoo.org>, various fixes
33 .\" 2007-12-08, mtk, Converted from mdoc to man macros
35 .TH ELF 5 2016-03-15 "Linux" "Linux Programmer's Manual"
37 elf \- format of Executable and Linking Format (ELF) files
40 .\" .B #include <elf_abi.h>
46 defines the format of ELF executable binary files.
47 Amongst these files are
48 normal executable files, relocatable object files, core files, and shared
51 An executable file using the ELF file format consists of an ELF header,
52 followed by a program header table or a section header table, or both.
53 The ELF header is always at offset zero of the file.
55 table and the section header table's offset in the file are defined in the
57 The two tables describe the rest of the particularities of
60 .\" Applications which wish to process ELF binary files for their native
61 .\" architecture only should include
63 .\" in their source code.
64 .\" These applications should need to refer to
65 .\" all the types and structures by their generic names
67 .\" and to the macros by
69 .\" Applications written this way can be compiled on any architecture,
70 .\" regardless of whether the host is 32-bit or 64-bit.
72 .\" Should an application need to process ELF files of an unknown
73 .\" architecture, then the application needs to explicitly use either
77 .\" type and structure names.
78 .\" Likewise, the macros need to be identified by
83 This header file describes the above mentioned headers as C structures
84 and also includes structures for dynamic sections, relocation sections and
87 The following types are used for N-bit architectures (N=32,64,
101 ElfN_Addr Unsigned program address, uintN_t
102 ElfN_Off Unsigned file offset, uintN_t
103 ElfN_Section Unsigned section index, uint16_t
104 ElfN_Versym Unsigned version symbol information, uint16_t
105 Elf_Byte unsigned char
111 .\" Elf32_Size Unsigned object size
115 (Note: The *BSD terminology is a bit different.
125 In order to avoid confusion these types are replaced by explicit ones
128 All data structures that the file format defines follow the
130 size and alignment guidelines for the relevant class.
132 data structures contain explicit padding to ensure 4-byte alignment
133 for 4-byte objects, to force structure sizes to a multiple of 4, and so on.
135 The ELF header is described by the type
145 unsigned char e_ident[EI_NIDENT];
154 uint16_t e_phentsize;
156 uint16_t e_shentsize;
163 The fields have the following meanings:
169 This array of bytes specifies how to interpret the file,
170 independent of the processor or the file's remaining contents.
171 Within this array everything is named by macros, which start with
174 and may contain values which start with the prefix
176 The following macros are defined:
180 The first byte of the magic number.
181 It must be filled with
186 The second byte of the magic number.
187 It must be filled with
192 The third byte of the magic number.
193 It must be filled with
198 The fourth byte of the magic number.
199 It must be filled with
204 The fifth byte identifies the architecture for this binary:
209 This class is invalid.
212 This defines the 32-bit architecture.
213 It supports machines with files
214 and virtual address spaces up to 4 Gigabytes.
217 This defines the 64-bit architecture.
222 The sixth byte specifies the data encoding of the processor-specific
224 Currently, these encodings are supported:
232 Two's complement, little-endian.
235 Two's complement, big-endian.
241 The seventh byte is the version number of the ELF specification:
255 The eighth byte identifies the operating system
256 and ABI to which the object is targeted.
257 Some fields in other ELF structures have flags
258 and values that have platform-specific meanings;
259 the interpretation of those fields is determined by the value of this byte.
265 Same as ELFOSABI_SYSV
271 .\" synonym: ELFOSABI_NONE
285 .\" .BR ELFOSABI_HURD
289 .\" .BR ELFOSABI_86OPEN
290 .\" 86Open Common IA32 ABI
297 .\" .BR ELFOSABI_MONTEREY
298 .\" Monterey project ABI
323 .BR ELFOSABI_STANDALONE
324 Stand-alone (embedded) ABI
330 The ninth byte identifies the version of the ABI
331 to which the object is targeted.
332 This field is used to distinguish among incompatible versions of an ABI.
333 The interpretation of this version number
334 is dependent on the ABI identified by the
337 Applications conforming to this specification use the value 0.
341 These bytes are reserved and set to zero.
343 which read them should ignore them.
347 the future if currently unused bytes are given meanings.
348 .\" As reported by Yuri Kozlov and confirmed by Mike Frysinger, EI_BRAND is
349 .\" not in GABI (http://www.sco.com/developers/gabi/latest/ch4.eheader.html)
350 .\" It looks to be a BSDism
353 .\" Start of architecture identification.
362 This member of the structure identifies the object file type:
384 This member specifies the required architecture for an individual file.
398 Sun Microsystems SPARC
422 MIPS RS3000 (big-endian only)
427 .\" .BR EM_MIPS_RS4_BE
428 .\" MIPS RS4000 (big-endian only). Deprecated
430 .\" EM_MIPS_RS3_LE (MIPS R3000 little-endian)
438 SPARC with enhanced instruction set
454 Advanced RISC Machines
480 .\" Compaq [DEC] Alpha
483 .\" Compaq [DEC] Alpha with enhanced instruction set
488 This member identifies the file version:
501 This member gives the virtual address to which the system first transfers
502 control, thus starting the process.
503 If the file has no associated entry
504 point, this member holds zero.
507 This member holds the program header table's file offset in bytes.
509 the file has no program header table, this member holds zero.
512 This member holds the section header table's file offset in bytes.
514 file has no section header table, this member holds zero.
517 This member holds processor-specific flags associated with the file.
518 Flag names take the form EF_`machine_flag'.
519 Currently, no flags have been defined.
522 This member holds the ELF header's size in bytes.
525 This member holds the size in bytes of one entry in the file's program header
526 table; all entries are the same size.
529 This member holds the number of entries in the program header
535 gives the table's size
537 If a file has no program header,
539 holds the value zero.
541 If the number of entries in the program header table is larger than or equal to
542 .\" This is a Linux extension, added in Linux 2.6.34.
544 (0xffff), this member holds
546 (0xffff) and the real number of entries in the program header table is held
549 member of the initial entry in section header table.
552 member of the initial entry contains the value zero.
556 This is defined as 0xffff, the largest number
558 can have, specifying where the actual number of program headers is assigned.
564 This member holds a sections header's size in bytes.
565 A section header is one
566 entry in the section header table; all entries are the same size.
569 This member holds the number of entries in the section header table.
575 gives the section header table's size in bytes.
576 If a file has no section
579 holds the value of zero.
581 If the number of entries in the section header table is larger than or equal to
585 holds the value zero and the real number of entries in the section header
588 member of the initial entry in section header table.
591 member of the initial entry in the section header table holds the value zero.
594 This member holds the section header table index of the entry associated
595 with the section name string table.
596 If the file has no section name string
597 table, this member holds the value
600 If the index of section name string table section is larger than or equal to
602 (0xff00), this member holds
604 (0xffff) and the real index of the section name string table section
607 member of the initial entry in section header table.
610 member of the initial entry in section header table contains the value zero.
612 An executable or shared object file's program header table is an array of
613 structures, each describing a segment or other information the system needs
614 to prepare the program for execution.
619 Program headers are meaningful only for executable and shared object files.
620 A file specifies its own program header size with the ELF header's
625 The ELF program header is described by the type
629 depending on the architecture:
661 The main difference between the 32-bit and the 64-bit program header lies
662 in the location of the
664 member in the total struct.
667 This member of the structure indicates what kind of segment this array
668 element describes or how to interpret the array element's information.
672 The array element is unused and the other members' values are undefined.
673 This lets the program header have ignored entries.
676 The array element specifies a loadable segment, described by
680 The bytes from the file are mapped to the beginning of the memory
682 If the segment's memory size
684 is larger than the file size
688 bytes are defined to hold the value 0 and to follow the segment's
690 The file size may not be larger than the memory size.
691 Loadable segment entries in the program header table appear in ascending
697 The array element specifies dynamic linking information.
700 The array element specifies the location and size of a null-terminated
701 pathname to invoke as an interpreter.
702 This segment type is meaningful
703 only for executable files (though it may occur for shared objects).
704 However it may not occur more than once in a file.
705 If it is present, it must precede any loadable segment entry.
708 The array element specifies the location and size for auxiliary information.
711 This segment type is reserved but has unspecified semantics.
713 contain an array element of this type do not conform to the ABI.
716 The array element, if present, specifies the location and size of the program
717 header table itself, both in the file and in the memory image of the program.
718 This segment type may not occur more than once in a file.
720 occur only if the program header table is part of the memory image of the
722 If it is present, it must precede any loadable segment entry.
724 .BR PT_LOPROC ", " PT_HIPROC
725 Values in the inclusive range
726 .RB [ PT_LOPROC ", " PT_HIPROC ]
727 are reserved for processor-specific semantics.
730 GNU extension which is used by the Linux kernel to control the state of the
731 stack via the flags set in the
737 This member holds the offset from the beginning of the file at which
738 the first byte of the segment resides.
741 This member holds the virtual address at which the first byte of the
742 segment resides in memory.
745 On systems for which physical addressing is relevant, this member is
746 reserved for the segment's physical address.
750 not used and must be zero.
753 This member holds the number of bytes in the file image of the segment.
757 This member holds the number of bytes in the memory image of the segment.
761 This member holds a bit mask of flags relevant to the segment:
766 An executable segment.
776 A text segment commonly has the flags
780 A data segment commonly has
787 This member holds the value to which the segments are aligned in memory
789 Loadable process segments must have congruent values for
793 modulo the page size.
794 Values of zero and one mean no alignment is required.
797 should be a positive, integral power of two, and
804 A file's section header table lets one locate all the file's sections.
806 section header table is an array of
814 member gives the byte offset from the beginning of the file to the section
817 holds the number of entries the section header table contains.
819 holds the size in bytes of each entry.
821 A section header table index is a subscript into this array.
823 header table indices are reserved:
824 the initial entry and the indices between
828 The initial entry is used in ELF extensions for
833 in other cases, each field in the initial entry is set to zero.
834 An object file does not have sections for
835 these special indices:
838 This value marks an undefined, missing, irrelevant, or otherwise meaningless
842 This value specifies the lower bound of the range of reserved indices.
844 .BR SHN_LOPROC ", " SHN_HIPROC
845 Values greater in the inclusive range
846 .RB [ SHN_LOPROC ", " SHN_HIPROC ]
847 are reserved for processor-specific semantics.
850 This value specifies the absolute value for the corresponding reference.
852 example, a symbol defined relative to section number
854 has an absolute value and is not affected by relocation.
857 Symbols defined relative to this section are common symbols, such as FORTRAN
858 COMMON or unallocated C external variables.
861 This value specifies the upper bound of the range of reserved indices.
863 system reserves indices between
868 The section header table does not contain entries for the
871 The section header has the following structure:
884 uint32_t sh_addralign;
901 uint64_t sh_addralign;
907 No real differences exist between the 32-bit and 64-bit section headers.
910 This member specifies the name of the section.
911 Its value is an index
912 into the section header string table section, giving the location of
913 a null-terminated string.
916 This member categorizes the section's contents and semantics.
920 This value marks the section header as inactive.
922 have an associated section.
923 Other members of the section header
924 have undefined values.
927 This section holds information defined by the program, whose
928 format and meaning are determined solely by the program.
931 This section holds a symbol table.
934 provides symbols for link editing, though it may also be used
936 As a complete symbol table, it may contain
937 many symbols unnecessary for dynamic linking.
944 This section holds a string table.
945 An object file may have multiple
946 string table sections.
949 This section holds relocation entries with explicit addends, such
952 for the 32-bit class of object files.
953 An object may have multiple
957 This section holds a symbol hash table.
958 An object participating in
959 dynamic linking must contain a symbol hash table.
961 have only one hash table.
964 This section holds information for dynamic linking.
966 have only one dynamic section.
969 This section holds information that marks the file in some way.
972 A section of this type occupies no space in the file but otherwise
975 Although this section contains no bytes, the
977 member contains the conceptual file offset.
980 This section holds relocation offsets without explicit addends, such
983 for the 32-bit class of object files.
984 An object file may have multiple
988 This section is reserved but has unspecified semantics.
991 This section holds a minimal set of dynamic linking symbols.
993 object file can also contain a
997 .BR SHT_LOPROC ", " SHT_HIPROC
998 Values in the inclusive range
999 .RB [ SHT_LOPROC ", " SHT_HIPROC ]
1000 are reserved for processor-specific semantics.
1003 This value specifies the lower bound of the range of indices reserved for
1004 application programs.
1007 This value specifies the upper bound of the range of indices reserved for
1008 application programs.
1009 Section types between
1013 may be used by the application, without conflicting with current or future
1014 system-defined section types.
1018 Sections support one-bit flags that describe miscellaneous attributes.
1019 If a flag bit is set in
1024 Otherwise, the attribute is
1027 Undefined attributes are set to zero.
1031 This section contains data that should be writable during process
1035 This section occupies memory during process execution.
1037 sections do not reside in the memory image of an object file.
1039 attribute is off for those sections.
1042 This section contains executable machine instructions.
1045 All bits included in this mask are reserved for processor-specific
1050 If this section appears in the memory image of a process, this member
1051 holds the address at which the section's first byte should reside.
1052 Otherwise, the member contains zero.
1055 This member's value holds the byte offset from the beginning of the file
1056 to the first byte in the section.
1059 occupies no space in the file, and its
1061 member locates the conceptual placement in the file.
1064 This member holds the section's size in bytes.
1065 Unless the section type
1068 the section occupies
1073 may have a nonzero size, but it occupies no space in the file.
1076 This member holds a section header table index link, whose interpretation
1077 depends on the section type.
1080 This member holds extra information, whose interpretation depends on the
1084 Some sections have address alignment constraints.
1085 If a section holds a
1086 doubleword, the system must ensure doubleword alignment for the entire
1088 That is, the value of
1090 must be congruent to zero, modulo the value of
1092 Only zero and positive integral powers of two are allowed.
1094 or one mean the section has no alignment constraints.
1097 Some sections hold a table of fixed-sized entries, such as a symbol table.
1098 For such a section, this member gives the size in bytes for each entry.
1099 This member contains zero if the section does not hold a table of
1102 Various sections hold program and control information:
1105 This section holds uninitialized data that contributes to the program's
1107 By definition, the system initializes the data with zeros
1108 when the program begins to run.
1109 This section is of type
1111 The attribute types are
1117 This section holds version control information.
1118 This section is of type
1120 No attribute types are used.
1123 This section holds initialized pointers to the C++ constructor functions.
1124 This section is of type
1126 The attribute types are
1132 This section holds initialized data that contribute to the program's
1134 This section is of type
1136 The attribute types are
1142 This section holds initialized data that contribute to the program's
1144 This section is of type
1146 The attribute types are
1152 This section holds information for symbolic debugging.
1155 This section is of type
1157 No attribute types are used.
1160 This section holds initialized pointers to the C++ destructor functions.
1161 This section is of type
1163 The attribute types are
1169 This section holds dynamic linking information.
1170 The section's attributes
1176 bit is set is processor-specific.
1177 This section is of type
1179 See the attributes above.
1182 This section holds strings needed for dynamic linking, most commonly
1183 the strings that represent the names associated with symbol table entries.
1184 This section is of type
1186 The attribute type used is
1190 This section holds the dynamic linking symbol table.
1191 This section is of type
1193 The attribute used is
1197 This section holds executable instructions that contribute to the process
1199 When a program exits normally the system arranges to
1200 execute the code in this section.
1201 This section is of type
1203 The attributes used are
1209 This section holds the version symbol table, an array of
1212 This section is of type
1213 .BR SHT_GNU_versym .
1214 The attribute type used is
1218 This section holds the version symbol definitions, a table of
1221 This section is of type
1222 .BR SHT_GNU_verdef .
1223 The attribute type used is
1227 This section holds the version symbol needed elements, a table of
1232 .BR SHT_GNU_versym .
1233 The attribute type used is
1237 This section holds the global offset table.
1238 This section is of type
1240 The attributes are processor-specific.
1243 This section holds a symbol hash table.
1244 This section is of type
1246 The attribute used is
1250 This section holds executable instructions that contribute to the process
1251 initialization code.
1252 When a program starts to run the system arranges to
1253 execute the code in this section before calling the main program entry point.
1254 This section is of type
1256 The attributes used are
1262 This section holds the pathname of a program interpreter.
1264 a loadable segment that includes the section, the section's attributes will
1268 Otherwise, that bit will be off.
1269 This section is of type
1273 This section holds line number information for symbolic debugging, which
1274 describes the correspondence between the program source and the machine code.
1275 The contents are unspecified.
1276 This section is of type
1278 No attribute types are used.
1281 This section holds information in the
1284 This section is of type
1286 No attribute types are used.
1288 native executables usually contain a
1289 .I .note.openbsd.ident
1290 section to identify themselves, for the kernel to bypass any compatibility
1291 ELF binary emulation tests when loading the file.
1294 This section is used in Linux object files for declaring stack attributes.
1295 This section is of type
1297 The only attribute used is
1299 This indicates to the GNU linker that the object file requires an
1303 This section holds the procedure linkage table.
1304 This section is of type
1306 The attributes are processor-specific.
1309 This section holds relocation information as described below.
1311 has a loadable segment that includes relocation, the section's attributes
1315 Otherwise, the bit will be off.
1318 is supplied by the section to which the relocations apply.
1322 normally would have the name
1324 This section is of type
1328 This section holds relocation information as described below.
1330 has a loadable segment that includes relocation, the section's attributes
1334 Otherwise, the bit will be off.
1337 is supplied by the section to which the relocations apply.
1341 normally would have the name
1343 This section is of type
1347 This section holds read-only data that typically contributes to a
1348 nonwritable segment in the process image.
1349 This section is of type
1351 The attribute used is
1355 This section holds read-only data that typically contributes to a
1356 nonwritable segment in the process image.
1357 This section is of type
1359 The attribute used is
1363 This section holds section names.
1364 This section is of type
1366 No attribute types are used.
1369 This section holds strings, most commonly the strings that represent the
1370 names associated with symbol table entries.
1371 If the file has a loadable
1372 segment that includes the symbol string table, the section's attributes
1376 Otherwise, the bit will be off.
1377 This section is of type
1381 This section holds a symbol table.
1382 If the file has a loadable segment
1383 that includes the symbol table, the section's attributes will include
1387 Otherwise, the bit will be off.
1388 This section is of type
1392 This section holds the
1394 or executable instructions, of a program.
1395 This section is of type
1397 The attributes used are
1402 String table sections hold null-terminated character sequences, commonly
1404 The object file uses these strings to represent symbol
1406 One references a string as an index into the string
1408 The first byte, which is index zero, is defined to hold
1409 a null byte (\(aq\\0\(aq).
1410 Similarly, a string table's last byte is defined to
1411 hold a null byte, ensuring null termination for all strings.
1413 An object file's symbol table holds information needed to locate and
1414 relocate a program's symbolic definitions and references.
1416 index is a subscript into this array.
1422 Elf32_Addr st_value;
1424 unsigned char st_info;
1425 unsigned char st_other;
1435 unsigned char st_info;
1436 unsigned char st_other;
1438 Elf64_Addr st_value;
1444 The 32-bit and 64-bit versions have the same members, just in a different
1448 This member holds an index into the object file's symbol string table,
1449 which holds character representations of the symbol names.
1451 is nonzero, it represents a string table index that gives the symbol
1453 Otherwise, the symbol has no name.
1456 This member gives the value of the associated symbol.
1459 Many symbols have associated sizes.
1460 This member holds zero if the symbol
1461 has no size or an unknown size.
1464 This member specifies the symbol's type and binding attributes:
1468 The symbol's type is not defined.
1471 The symbol is associated with a data object.
1474 The symbol is associated with a function or other executable code.
1477 The symbol is associated with a section.
1478 Symbol table entries of
1479 this type exist primarily for relocation and normally have
1484 By convention, the symbol's name gives the name of the source file
1485 associated with the object file.
1488 bindings, its section index is
1490 and it precedes the other
1492 symbols of the file, if it is present.
1494 .BR STT_LOPROC ", " STT_HIPROC
1495 Values in the inclusive range
1496 .RB [ STT_LOPROC ", " STT_HIPROC ]
1497 are reserved for processor-specific semantics.
1500 Local symbols are not visible outside the object file containing their
1502 Local symbols of the same name may exist in multiple files
1503 without interfering with each other.
1506 Global symbols are visible to all object files being combined.
1508 definition of a global symbol will satisfy another file's undefined
1509 reference to the same symbol.
1512 Weak symbols resemble global symbols, but their definitions have lower
1515 .BR STB_LOPROC ", " STB_HIPROC
1516 Values in the inclusive range
1517 .RB [ STB_LOPROC ", " STB_HIPROC ]
1518 are reserved for processor-specific semantics.
1521 There are macros for packing and unpacking the binding and type fields:
1524 .BR ELF32_ST_BIND( \fIinfo\fP ) ", " ELF64_ST_BIND( \fIinfo\fP )
1525 Extract a binding from an
1529 .BR ELF32_ST_TYPE( \fIinfo ) ", " ELF64_ST_TYPE( \fIinfo\fP )
1530 Extract a type from an
1534 .BR ELF32_ST_INFO( \fIbind\fP ", " \fItype\fP ) ", " \
1535 ELF64_ST_INFO( \fIbind\fP ", " \fItype\fP )
1536 Convert a binding and a type into an
1542 This member defines the symbol visibility.
1547 Default symbol visibility rules.
1548 Global and weak symbols are available to other modules;
1549 references in the local module can be interposed
1550 by definitions in other modules.
1553 Processor-specific hidden class.
1556 Symbol is unavailable to other modules;
1557 references in the local module always resolve to the local symbol
1558 (i.e., the symbol can't be interposed by definitions in other modules).
1561 Symbol is available to other modules,
1562 but references in the local module always resolve to the local symbol.
1565 There are macros for extracting the visibility type:
1567 .BR ELF32_ST_VISIBILITY (other)
1569 .BR ELF64_ST_VISIBILITY (other)
1573 Every symbol table entry is
1575 in relation to some section.
1576 This member holds the relevant section
1579 Relocation is the process of connecting symbolic references with
1580 symbolic definitions.
1581 Relocatable files must have information that
1582 describes how to modify their section contents, thus allowing executable
1583 and shared object files to hold the right information for a process's
1585 Relocation entries are these data.
1587 Relocation structures that do not need an addend:
1592 Elf32_Addr r_offset;
1601 Elf64_Addr r_offset;
1607 Relocation structures that need an addend:
1612 Elf32_Addr r_offset;
1622 Elf64_Addr r_offset;
1630 This member gives the location at which to apply the relocation action.
1631 For a relocatable file, the value is the byte offset from the beginning
1632 of the section to the storage unit affected by the relocation.
1634 executable file or shared object, the value is the virtual address of
1635 the storage unit affected by the relocation.
1638 This member gives both the symbol table index with respect to which the
1639 relocation must be made and the type of relocation to apply.
1641 types are processor-specific.
1642 When the text refers to a relocation
1643 entry's relocation type or symbol table index, it means the result of
1645 .BR ELF[32|64]_R_TYPE
1647 .BR ELF[32|64]_R_SYM ,
1648 respectively, to the entry's
1653 This member specifies a constant addend used to compute the value to be
1654 stored into the relocatable field.
1658 section contains a series of structures that hold relevant
1659 dynamic linking information.
1662 member controls the interpretation
1675 extern Elf32_Dyn _DYNAMIC[];
1688 extern Elf64_Dyn _DYNAMIC[];
1693 This member may have any of the following values:
1697 Marks end of dynamic section
1700 String table offset to name of a needed library
1703 Size in bytes of PLT relocation entries
1706 Address of PLT and/or GOT
1709 Address of symbol hash table
1712 Address of string table
1715 Address of symbol table
1718 Address of Rela relocation table
1721 Size in bytes of the Rela relocation table
1724 Size in bytes of a Rela relocation table entry
1727 Size in bytes of string table
1730 Size in bytes of a symbol table entry
1733 Address of the initialization function
1736 Address of the termination function
1739 String table offset to name of shared object
1742 String table offset to library search path (deprecated)
1745 Alert linker to search this shared object before the executable for symbols
1748 Address of Rel relocation table
1751 Size in bytes of Rel relocation table
1754 Size in bytes of a Rel table entry
1757 Type of relocation entry to which the PLT refers (Rela or Rel)
1760 Undefined use for debugging
1763 Absence of this entry indicates that no relocation entries should
1764 apply to a nonwritable segment
1767 Address of relocation entries associated solely with the PLT
1770 Instruct dynamic linker to process all relocations before
1771 transferring control to the executable
1774 String table offset to library search path
1776 .BR DT_LOPROC ", " DT_HIPROC
1777 Values in the inclusive range
1778 .RB [ DT_LOPROC ", " DT_HIPROC ]
1779 are reserved for processor-specific semantics
1783 This member represents integer values with various interpretations.
1786 This member represents program virtual addresses.
1788 these addresses, the actual address should be computed based on the
1789 original file value and memory base address.
1790 Files do not contain
1791 relocation entries to fixup these addresses.
1794 Array containing all the dynamic structures in the
1797 This is automatically populated by the linker.
1800 .\" ELF support first appeared in
1802 .\" although not all supported platforms use it as the native
1803 .\" binary file format.
1804 ELF first appeared in
1806 The ELF format is an adopted standard.
1815 Sun, BSD and AMD64 also support them; for further information,
1816 look under SEE ALSO.
1818 .\" The original version of this manual page was written by
1819 .\" .An Jeroen Ruigrok van der Werven
1820 .\" .Aq asmodai@FreeBSD.org
1821 .\" with inspiration from BSDi's
1835 .IR "Elf-64 Object File Format" .
1837 Santa Cruz Operation,
1838 .IR "System V Application Binary Interface" .
1840 UNIX System Laboratories,
1842 .IR "Executable and Linking Format (ELF)" .
1845 .IR "Linker and Libraries Guide" .
1848 .IR "System V Application Binary Interface AMD64 Architecture Processor Supplement" .
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