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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COPYRIGHT | COLOPHON |
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READELF(1) GNU Development Tools READELF(1)
readelf - display information about ELF files
readelf [-a|--all]
[-h|--file-header]
[-l|--program-headers|--segments]
[-S|--section-headers|--sections]
[-g|--section-groups]
[-t|--section-details]
[-e|--headers]
[-s|--syms|--symbols]
[--dyn-syms|--lto-syms]
[--sym-base=[0|8|10|16]]
[--demangle=style|--no-demangle]
[--quiet]
[--recurse-limit|--no-recurse-limit]
[-U method|--unicode=method]
[-X|--extra-sym-info|--no-extra-sym-info]
[-n|--notes]
[-r|--relocs]
[-u|--unwind]
[-d|--dynamic]
[-V|--version-info]
[-A|--arch-specific]
[-D|--use-dynamic]
[-L|--lint|--enable-checks]
[-x <number or name>|--hex-dump=<number or name>]
[-p <number or name>|--string-dump=<number or name>]
[-R <number or name>|--relocated-dump=<number or name>]
[-j <number or name>|--display-section=<number or name>]
[-z|--decompress]
[-c|--archive-index]
[-w[lLiaprmfFsoORtUuTgAck]|
--debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
[-wK|--debug-dump=follow-links]
[-wN|--debug-dump=no-follow-links]
[-wD|--debug-dump=use-debuginfod]
[-wE|--debug-dump=do-not-use-debuginfod]
[-P|--process-links]
[--dwarf-depth=n]
[--dwarf-start=n]
[--ctf=section]
[--ctf-parent=section]
[--ctf-symbols=section]
[--ctf-strings=section]
[--sframe=section]
[-I|--histogram]
[-v|--version]
[-W|--wide]
[-T|--silent-truncation]
[-H|--help]
elffile...
readelf displays information about one or more ELF format object
files. The options control what particular information to
display.
elffile... are the object files to be examined. 32-bit and 64-bit
ELF files are supported, as are archives containing ELF files.
This program performs a similar function to objdump but it goes
into more detail and it exists independently of the BFD library,
so if there is a bug in BFD then readelf will not be affected.
The long and short forms of options, shown here as alternatives,
are equivalent. At least one option besides -v or -H must be
given.
-a
--all
Equivalent to specifying --file-header, --program-headers,
--sections, --symbols, --relocs, --dynamic, --notes,
--version-info, --arch-specific, --unwind, --section-groups
and --histogram.
Note - this option does not enable --use-dynamic itself, so if
that option is not present on the command line then dynamic
symbols and dynamic relocs will not be displayed.
-h
--file-header
Displays the information contained in the ELF header at the
start of the file.
-l
--program-headers
--segments
Displays the information contained in the file's segment
headers, if it has any.
--quiet
Suppress "no symbols" diagnostic.
-S
--sections
--section-headers
Displays the information contained in the file's section
headers, if it has any.
-g
--section-groups
Displays the information contained in the file's section
groups, if it has any.
-t
--section-details
Displays the detailed section information. Implies -S.
-s
--symbols
--syms
Displays the entries in symbol table section of the file, if
it has one. If a symbol has version information associated
with it then this is displayed as well. The version string is
displayed as a suffix to the symbol name, preceded by an @
character. For example foo@VER_1. If the version is the
default version to be used when resolving unversioned
references to the symbol then it is displayed as a suffix
preceded by two @ characters. For example foo@@VER_2.
--dyn-syms
Displays the entries in dynamic symbol table section of the
file, if it has one. The output format is the same as the
format used by the --syms option.
--lto-syms
Displays the contents of any LTO symbol tables in the file.
--sym-base=[0|8|10|16]
Forces the size field of the symbol table to use the given
base. Any unrecognized options will be treated as 0.
--sym-base=0 represents the default and legacy behaviour.
This will output sizes as decimal for numbers less than
100000. For sizes 100000 and greater hexadecimal notation
will be used with a 0x prefix. --sym-base=8 will give the
symbol sizes in octal. --sym-base=10 will always give the
symbol sizes in decimal. --sym-base=16 will always give the
symbol sizes in hexadecimal with a 0x prefix.
-C
--demangle[=style]
Decode (demangle) low-level symbol names into user-level
names. This makes C++ function names readable. Different
compilers have different mangling styles. The optional
demangling style argument can be used to choose an appropriate
demangling style for your compiler.
--no-demangle
Do not demangle low-level symbol names. This is the default.
--recurse-limit
--no-recurse-limit
--recursion-limit
--no-recursion-limit
Enables or disables a limit on the amount of recursion
performed whilst demangling strings. Since the name mangling
formats allow for an infinite level of recursion it is
possible to create strings whose decoding will exhaust the
amount of stack space available on the host machine,
triggering a memory fault. The limit tries to prevent this
from happening by restricting recursion to 2048 levels of
nesting.
The default is for this limit to be enabled, but disabling it
may be necessary in order to demangle truly complicated names.
Note however that if the recursion limit is disabled then
stack exhaustion is possible and any bug reports about such an
event will be rejected.
-U [d|i|l|e|x|h]
--unicode=[default|invalid|locale|escape|hex|highlight]
Controls the display of non-ASCII characters in identifier
names. The default (--unicode=locale or --unicode=default) is
to treat them as multibyte characters and display them in the
current locale. All other versions of this option treat the
bytes as UTF-8 encoded values and attempt to interpret them.
If they cannot be interpreted or if the --unicode=invalid
option is used then they are displayed as a sequence of hex
bytes, encloses in curly parethesis characters.
Using the --unicode=escape option will display the characters
as as unicode escape sequences (\uxxxx). Using the
--unicode=hex will display the characters as hex byte
sequences enclosed between angle brackets.
Using the --unicode=highlight will display the characters as
unicode escape sequences but it will also highlighted them in
red, assuming that colouring is supported by the output
device. The colouring is intended to draw attention to the
presence of unicode sequences when they might not be expected.
-X
--extra-sym-info
When displaying details of symbols, include extra information
not normally presented. Currently this just adds the name of
the section referenced by the symbol's index field, if there
is one. In the future more information may be displayed when
this option is enabled.
Enabling this option effectively enables the --wide option as
well, at least when displaying symbol information.
--no-extra-sym-info
Disables the effect of the --extra-sym-info option. This is
the default.
-e
--headers
Display all the headers in the file. Equivalent to -h -l -S.
-n
--notes
Displays the contents of the NOTE segments and/or sections, if
any.
-r
--relocs
Displays the contents of the file's relocation section, if it
has one.
-u
--unwind
Displays the contents of the file's unwind section, if it has
one. Only the unwind sections for IA64 ELF files, as well as
ARM unwind tables (".ARM.exidx" / ".ARM.extab") are currently
supported. If support is not yet implemented for your
architecture you could try dumping the contents of the
.eh_frames section using the --debug-dump=frames or
--debug-dump=frames-interp options.
-d
--dynamic
Displays the contents of the file's dynamic section, if it has
one.
-V
--version-info
Displays the contents of the version sections in the file, it
they exist.
-A
--arch-specific
Displays architecture-specific information in the file, if
there is any.
-D
--use-dynamic
When displaying symbols, this option makes readelf use the
symbol hash tables in the file's dynamic section, rather than
the symbol table sections.
When displaying relocations, this option makes readelf display
the dynamic relocations rather than the static relocations.
-L
--lint
--enable-checks
Displays warning messages about possible problems with the
file(s) being examined. If used on its own then all of the
contents of the file(s) will be examined. If used with one of
the dumping options then the warning messages will only be
produced for the things being displayed.
-x <number or name>
--hex-dump=<number or name>
Displays the contents of the indicated section as a
hexadecimal bytes. A number identifies a particular section
by index in the section table; any other string identifies all
sections with that name in the object file. This option can
be repeated multiple times on the command line in order to
request multiple hex dumps.
-R <number or name>
--relocated-dump=<number or name>
Displays the contents of the indicated section as a
hexadecimal bytes. A number identifies a particular section
by index in the section table; any other string identifies all
sections with that name in the object file. The contents of
the section will be relocated before they are displayed. This
option can be repeated multiple times on the command line in
order to request multiple relocated dumps.
-p <number or name>
--string-dump=<number or name>
Displays the contents of the indicated section as printable
strings. A number identifies a particular section by index in
the section table; any other string identifies all sections
with that name in the object file. This option can be
repeated multiple times on the command line in order to
request multiple string dumps.
-j <number or name>
--display-section
Displays the contents of the indicated section according to
its section header type. Sections containing relocations will
be displayed as if the --relocations option had been used,
sections contains symbols will be displayed as if the --syms
option had been used and so on.
A number identifies a particular section by index in the
section table; any other string identifies all sections with
that name in the input file(s).
This option can be repeated multiple times on the command line
in order to request multiple section dumps.
-z
--decompress
Requests that the section(s) being dumped by x, R or p options
are decompressed before being displayed. If the section(s)
are not compressed then they are displayed as is.
-c
--archive-index
Displays the file symbol index information contained in the
header part of binary archives. Performs the same function as
the t command to ar, but without using the BFD library.
-w[lLiaprmfFsOoRtUuTgAckK]
--debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
Displays the contents of the DWARF debug sections in the file,
if any are present. Compressed debug sections are
automatically decompressed (temporarily) before they are
displayed. If one or more of the optional letters or words
follows the switch then only those type(s) of data will be
dumped. The letters and words refer to the following
information:
"a"
"=abbrev"
Displays the contents of the .debug_abbrev section.
"A"
"=addr"
Displays the contents of the .debug_addr section.
"c"
"=cu_index"
Displays the contents of the .debug_cu_index and/or
.debug_tu_index sections.
"f"
"=frames"
Display the raw contents of a .debug_frame section.
"F"
"=frames-interp"
Display the interpreted contents of a .debug_frame
section.
"g"
"=gdb_index"
Displays the contents of the .gdb_index and/or
.debug_names sections.
"i"
"=info"
Displays the contents of the .debug_info section. Note:
the output from this option can also be restricted by the
use of the --dwarf-depth and --dwarf-start options.
"k"
"=links"
Displays the contents of the .gnu_debuglink,
.gnu_debugaltlink and .debug_sup sections, if any of them
are present. Also displays any links to separate dwarf
object files (dwo), if they are specified by the
DW_AT_GNU_dwo_name or DW_AT_dwo_name attributes in the
.debug_info section.
"K"
"=follow-links"
Display the contents of any selected debug sections that
are found in linked, separate debug info file(s). This
can result in multiple versions of the same debug section
being displayed if it exists in more than one file.
In addition, when displaying DWARF attributes, if a form
is found that references the separate debug info file,
then the referenced contents will also be displayed.
Note - in some distributions this option is enabled by
default. It can be disabled via the N debug option. The
default can be chosen when configuring the binutils via
the --enable-follow-debug-links=yes or
--enable-follow-debug-links=no options. If these are not
used then the default is to enable the following of debug
links.
Note - if support for the debuginfod protocol was enabled
when the binutils were built then this option will also
include an attempt to contact any debuginfod servers
mentioned in the DEBUGINFOD_URLS environment variable.
This could take some time to resolve. This behaviour can
be disabled via the =do-not-use-debuginfod debug option.
"N"
"=no-follow-links"
Disables the following of links to separate debug info
files.
"D"
"=use-debuginfod"
Enables contacting debuginfod servers if there is a need
to follow debug links. This is the default behaviour.
"E"
"=do-not-use-debuginfod"
Disables contacting debuginfod servers when there is a
need to follow debug links.
"l"
"=rawline"
Displays the contents of the .debug_line section in a raw
format.
"L"
"=decodedline"
Displays the interpreted contents of the .debug_line
section.
"m"
"=macro"
Displays the contents of the .debug_macro and/or
.debug_macinfo sections.
"o"
"=loc"
Displays the contents of the .debug_loc and/or
.debug_loclists sections.
"O"
"=str-offsets"
Displays the contents of the .debug_str_offsets section.
"p"
"=pubnames"
Displays the contents of the .debug_pubnames and/or
.debug_gnu_pubnames sections.
"r"
"=aranges"
Displays the contents of the .debug_aranges section.
"R"
"=Ranges"
Displays the contents of the .debug_ranges and/or
.debug_rnglists sections.
"s"
"=str"
Displays the contents of the .debug_str, .debug_line_str
and/or .debug_str_offsets sections.
"t"
"=pubtype"
Displays the contents of the .debug_pubtypes and/or
.debug_gnu_pubtypes sections.
"T"
"=trace_aranges"
Displays the contents of the .trace_aranges section.
"u"
"=trace_abbrev"
Displays the contents of the .trace_abbrev section.
"U"
"=trace_info"
Displays the contents of the .trace_info section.
Note: displaying the contents of .debug_static_funcs,
.debug_static_vars and debug_weaknames sections is not
currently supported.
--dwarf-depth=n
Limit the dump of the ".debug_info" section to n children.
This is only useful with --debug-dump=info. The default is to
print all DIEs; the special value 0 for n will also have this
effect.
With a non-zero value for n, DIEs at or deeper than n levels
will not be printed. The range for n is zero-based.
--dwarf-start=n
Print only DIEs beginning with the DIE numbered n. This is
only useful with --debug-dump=info.
If specified, this option will suppress printing of any header
information and all DIEs before the DIE numbered n. Only
siblings and children of the specified DIE will be printed.
This can be used in conjunction with --dwarf-depth.
-P
--process-links
Display the contents of non-debug sections found in separate
debuginfo files that are linked to the main file. This option
automatically implies the -wK option, and only sections
requested by other command line options will be displayed.
--ctf[=section]
Display the contents of the specified CTF section. CTF
sections themselves contain many subsections, all of which are
displayed in order.
By default, display the name of the section named .ctf, which
is the name emitted by ld.
--ctf-parent=member
If the CTF section contains ambiguously-defined types, it will
consist of an archive of many CTF dictionaries, all inheriting
from one dictionary containing unambiguous types. This member
is by default named .ctf, like the section containing it, but
it is possible to change this name using the
"ctf_link_set_memb_name_changer" function at link time. When
looking at CTF archives that have been created by a linker
that uses the name changer to rename the parent archive
member, --ctf-parent can be used to specify the name used for
the parent.
--ctf-parent-section=section
This option lets you pick a completely different section for
the CTF parent dictionary containing unambiguous types than
for the child dictionaries that contain the ambiguous
remainder. The linker does not emit ELF objects structured
like this, but some third-party linkers may. It's also
convenient to inspect CTF written out as multiple raw files to
compose them with objcopy, which can put them in different ELF
sections but not in different members of a single CTF dict.
--ctf-symbols=section
--ctf-strings=section
Specify the name of another section from which the CTF file
can inherit strings and symbols. By default, the ".symtab"
and its linked string table are used.
If either of --ctf-symbols or --ctf-strings is specified, the
other must be specified as well.
-I
--histogram
Display a histogram of bucket list lengths when displaying the
contents of the symbol tables.
-v
--version
Display the version number of readelf.
-W
--wide
Don't break output lines to fit into 80 columns. By default
readelf breaks section header and segment listing lines for
64-bit ELF files, so that they fit into 80 columns. This
option causes readelf to print each section header resp. each
segment one a single line, which is far more readable on
terminals wider than 80 columns.
-T
--silent-truncation
Normally when readelf is displaying a symbol name, and it has
to truncate the name to fit into an 80 column display, it will
add a suffix of "[...]" to the name. This command line option
disables this behaviour, allowing 5 more characters of the
name to be displayed and restoring the old behaviour of
readelf (prior to release 2.35).
-H
--help
Display the command-line options understood by readelf.
@file
Read command-line options from file. The options read are
inserted in place of the original @file option. If file does
not exist, or cannot be read, then the option will be treated
literally, and not removed.
Options in file are separated by whitespace. A whitespace
character may be included in an option by surrounding the
entire option in either single or double quotes. Any
character (including a backslash) may be included by prefixing
the character to be included with a backslash. The file may
itself contain additional @file options; any such options will
be processed recursively.
objdump(1), and the Info entries for binutils.
Copyright (c) 1991-2025 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License,
Version 1.3 or any later version published by the Free Software
Foundation; with no Invariant Sections, with no Front-Cover Texts,
and with no Back-Cover Texts. A copy of the license is included
in the section entitled "GNU Free Documentation License".
This page is part of the binutils (a collection of tools for
working with executable binaries) project. Information about the
project can be found at ⟨http://www.gnu.org/software/binutils/⟩.
If you have a bug report for this manual page, see
⟨http://sourceware.org/bugzilla/enter_bug.cgi?product=binutils⟩.
This page was obtained from the tarball binutils-2.44.tar.gz
fetched from ⟨https://ftp.gnu.org/gnu/binutils/⟩ on 2025-02-02.
If you discover any rendering problems in this HTML version of the
page, or you believe there is a better or more up-to-date source
for the page, or you have corrections or improvements to the
information in this COLOPHON (which is not part of the original
manual page), send a mail to man-pages@man7.org
binutils-2.44 2025-02-02 READELF(1)
Pages that refer to this page: elfedit(1), ld(1), objdump(1), size(1), strings(1), dl_iterate_phdr(3), end(3), elf(5)
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HTML rendering created 2025-02-02 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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