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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]
	  [-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 fur-
	       ther 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 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  mem-
	   ber)	 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 com-
	   piler.

       --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	 file-
	   name and line number.  For a defined symbol, look for the line num-
	   ber of the address of the symbol.  For an  undefined	 symbol,  look
	   for	the line number of a relocation entry which refers to the sym-
	   bol.	 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 alphabeti-
	   cally 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 for-
	   mat.	 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 pro-
	   cessing 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 for-
	   mat.

       -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  charac-
	   ter	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 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".



binutils-2.17.50.0.6-26.el5	  2013-10-01				 NM(1)
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