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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]
	  [-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:

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

       o   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 weak	symbol
	       becomes zero with no error.

	   "-" 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.

       o   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.

       -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.

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

COPYRIGHT
       Copyright (c) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000,  2001,	 2002,
       2003 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-2.14.91		  2004-04-09				 NM(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COPYRIGHT

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