MirOS Manual: nm(1)


NM(1)                 GNU Development Tools                 NM(1)

NAME

     nm - list symbols from object files

SYNOPSIS

     nm [-a|--debug-syms] [-g|--extern-only]
        [-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" 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" The symbol is in the initialized data section.

         "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" The symbol is an indirect reference to another
             symbol.  This is a GNU extension to the a.out object

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             file format which is rarely used.

         "N" The symbol is a debugging symbol.

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

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

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

         "U" The symbol is undefined.

         "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.

         "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.

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     -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.

     -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

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         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 size, not the value, of defined symbols for the
         "bsd" output format.

     -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 transistions 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

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         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.

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 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 1.1 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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