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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