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NM(1)			     GNU Development Tools			 NM(1)

       nm - list symbols from object files

       nm [-a|--debug-syms] [-g|--extern-only]
	  [-B] [-C|--demangle[=style]] [-D|--dynamic]
	  [-S|--print-size] [-s|--print-armap]
	  [-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...]

       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 symbols 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

	   "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

	   "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

	   "-" 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.

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

	   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.

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

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

	   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

	   Do not demangle low-level symbol names.  This is the default.

	   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
	   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.

	   Display only external symbols.

	   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.

	   Sort symbols numerically by their addresses, rather than alphabeti
	   cally by their names.

	   Do not bother to sort the symbols in any order; print them  in  the
	   order encountered.

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

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

	   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.

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

	   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.

	   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  transistions  between  ARM
	   code, THUMB code and data.

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

	   Specify an object code format other than your systems default for

	   Display  only  undefined  symbols  (those  external	to each object

	   Display only defined symbols for each object file.

	   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.

	   Show a summary of the options to nm and exit.

	   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

	   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.

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

       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			  2006-06-23				 NM(1)

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