readelf(1)
NAME
readelf - Displays information about ELF files.
SYNOPSIS
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]
[-n|--notes]
[-r|--relocs]
[-u|--unwind]
[-d|--dynamic]
[-V|--version-info]
[-A|--arch-specific]
[-D|--use-dynamic]
[-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>]
[-z|--decompress]
[-c|--archive-index]
[-w[lLiaprmfFsoRt]|
--debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]]
[--dwarf-depth=n]
[--dwarf-start=n]
[-I|--histogram]
[-v|--version]
[-W|--wide]
[-H|--help]
elffile...
DESCRIPTION
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.
OPTIONS
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 and
--version-info.
-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.
-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, preceeded 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 preceeded 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.
-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.
-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.
-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.
-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.
-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.
-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[lLiaprmfFsoRt]
--debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]
Displays the contents of the debug sections in the file, if any are
present. If one of the optional letters or words follows the
switch then only data found in those specific sections will be
dumped.
Note that there is no single letter option to display the content
of trace sections or .gdb_index.
Note: the =decodedline option will display the interpreted contents
of a .debug_line section whereas the =rawline option dumps the
contents in a raw format.
Note: the =frames-interp option will display the interpreted
contents of a .debug_frame section whereas the =frames option dumps
the contents in a raw format.
Note: the output from the =info option can also be affected by the
options --dwarf-depth and --dwarf-start.
--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.
-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.
-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.
SEE ALSO
objdump(1), and the Info entries for binutils.
COPYRIGHT
Copyright (c) 1991-2016 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".
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