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NM(1)                        GNU Development Tools                       NM(1)



NAME
       nm - list symbols from object files

SYNOPSIS
       nm [-a|--debug-syms]
          [-g|--extern-only][--plugin name]
          [-B] [-C|--demangle[=style]] [-D|--dynamic]
          [-S|--print-size] [-s|--print-armap]
          [-A|-o|--print-file-name][--special-syms]
          [-n|-v|--numeric-sort] [-p|--no-sort]
          [-r|--reverse-sort] [--size-sort] [-u|--undefined-only]
          [-t radix|--radix=radix] [-P|--portability]
          [--target=bfdname] [-fformat|--format=format]
          [--defined-only] [-l|--line-numbers] [--no-demangle]
          [-V|--version] [-X 32_64] [--help]  [objfile...]

DESCRIPTION
       GNU nm lists the symbols from object files objfile....  If no object files are listed as arguments, nm assumes
       the file a.out.

       For each symbol, nm shows:

       ?   The symbol value, in the radix selected by options (see below), or hexadecimal by default.

       ?   The symbol type.  At least the following types are used; others are, as well, depending on the object file
           format.  If lowercase, the symbol is local; if uppercase, the symbol is global (external).

           "A" The symbol's value is absolute, and will not be changed by further linking.

           "B"
           "b" The symbol is in the uninitialized data section (known as BSS).

           "C" The symbol is common.  Common symbols are uninitialized data.  When linking, multiple common symbols
               may appear with the same name.  If the symbol is defined anywhere, the common symbols are treated as
               undefined references.

           "D"
           "d" The symbol is in the initialized data section.

           "G"
           "g" The symbol is in an initialized data section for small objects.  Some object file formats permit more
               efficient access to small data objects, such as a global int variable as opposed to a large global
               array.

           "i" For PE format files this indicates that the symbol is in a section specific to the implementation of
               DLLs.  For ELF format files this indicates that the symbol is an indirect function.  This is a GNU
               extension to the standard set of ELF symbol types.  It indicates a symbol which if referenced by a
               relocation does not evaluate to its address, but instead must be invoked at runtime.  The runtime
               execution will then return the value to be used in the relocation.

           "N" The symbol is a debugging symbol.

           "p" The symbols is in a stack unwind section.

           "R"
           "r" The symbol is in a read only data section.

           "S"
           "s" The symbol is in an uninitialized data section for small objects.

           "T"
           "t" The symbol is in the text (code) section.

           "U" The symbol is undefined.

           "u" The symbol is a unique global symbol.  This is a GNU extension to the standard set of ELF symbol
               bindings.  For such a symbol the dynamic linker will make sure that in the entire process there is just
               one symbol with this name and type in use.

           "V"
           "v" The symbol is a weak object.  When a weak defined symbol is linked with a normal defined symbol, the
               normal defined symbol is used with no error.  When a weak undefined symbol is linked and the symbol is
               not defined, the value of the weak symbol becomes zero with no error.  On some systems, uppercase
               indicates that a default value has been specified.

           "W"
           "w" The symbol is a weak symbol that has not been specifically tagged as a weak object symbol.  When a weak
               defined symbol is linked with a normal defined symbol, the normal defined symbol is used with no error.
               When a weak undefined symbol is linked and the symbol is not defined, the value of the symbol is
               determined in a system-specific manner without error.  On some systems, uppercase indicates that a
               default value has been specified.

           "-" The symbol is a stabs symbol in an a.out object file.  In this case, the next values printed are the
               stabs other field, the stabs desc field, and the stab type.  Stabs symbols are used to hold debugging
               information.

           "?" The symbol type is unknown, or object file format specific.

       ?   The symbol name.

OPTIONS
       The long and short forms of options, shown here as alternatives, are equivalent.

       -A
       -o
       --print-file-name
           Precede each symbol by the name of the input file (or archive member) in which it was found, rather than
           identifying the input file once only, before all of its symbols.

       -a
       --debug-syms
           Display all symbols, even debugger-only symbols; normally these are not listed.

       -B  The same as --format=bsd (for compatibility with the MIPS nm).

       -C
       --demangle[=style]
           Decode (demangle) low-level symbol names into user-level names.  Besides removing any initial underscore
           prepended by the system, 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.

       -D
       --dynamic
           Display the dynamic symbols rather than the normal symbols.  This is only meaningful for dynamic objects,
           such as certain types of shared libraries.

       -f format
       --format=format
           Use the output format format, which can be "bsd", "sysv", or "posix".  The default is "bsd".  Only the
           first character of format is significant; it can be either upper or lower case.

       -g
       --extern-only
           Display only external symbols.

       --plugin name
           Load the plugin called name to add support for extra target types.  This option is only available if the
           toolchain has been built with plugin support enabled.

       -l
       --line-numbers
           For each symbol, use debugging information to try to find a filename and line number.  For a defined
           symbol, look for the line number of the address of the symbol.  For an undefined symbol, look for the line
           number of a relocation entry which refers to the symbol.  If line number information can be found, print it
           after the other symbol information.

       -n
       -v
       --numeric-sort
           Sort symbols numerically by their addresses, rather than alphabetically by their names.

       -p
       --no-sort
           Do not bother to sort the symbols in any order; print them in the order encountered.

       -P
       --portability
           Use the POSIX.2 standard output format instead of the default format.  Equivalent to -f posix.

       -S
       --print-size
           Print both value and size of defined symbols for the "bsd" output style.  This option has no effect for
           object formats that do not record symbol sizes, unless --size-sort is also used in which case a calculated
           size is displayed.

       -s
       --print-armap
           When listing symbols from archive members, include the index: a mapping (stored in the archive by ar or
           ranlib) of which modules contain definitions for which names.

       -r
       --reverse-sort
           Reverse the order of the sort (whether numeric or alphabetic); let the last come first.

       --size-sort
           Sort symbols by size.  The size is computed as the difference between the value of the symbol and the value
           of the symbol with the next higher value.  If the "bsd" output format is used the size of the symbol is
           printed, rather than the value, and -S must be used in order both size and value to be printed.

       --special-syms
           Display symbols which have a target-specific special meaning.  These symbols are usually used by the target
           for some special processing and are not normally helpful when included included in the normal symbol lists.
           For example for ARM targets this option would skip the mapping symbols used to mark transitions between ARM
           code, THUMB code and data.

       -t radix
       --radix=radix
           Use radix as the radix for printing the symbol values.  It must be d for decimal, o for octal, or x for
           hexadecimal.

       --target=bfdname
           Specify an object code format other than your system's default format.

       -u
       --undefined-only
           Display only undefined symbols (those external to each object file).

       --defined-only
           Display only defined symbols for each object file.

       -V
       --version
           Show the version number of nm and exit.

       -X  This option is ignored for compatibility with the AIX version of nm.  It takes one parameter which must be
           the string 32_64.  The default mode of AIX nm corresponds to -X 32, which is not supported by GNU nm.

       --help
           Show a summary of the options to nm and exit.

       @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
       ar(1), objdump(1), ranlib(1), and the Info entries for binutils.

COPYRIGHT
       Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
       2007, 2008, 2009 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".



binutils-2.20.51.0.2              2017-04-11                             NM(1)