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NM(1)

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NAME    [Toc]    [Back]

       nm - list symbols from object files

SYNOPSIS    [Toc]    [Back]

       nm [-a|--debug-syms] [-g|--extern-only]
	  [-B] [-C|--demangle[=style]] [-D|--dynamic]
	  [-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    [Toc]    [Back]

       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 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 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    [Toc]    [Back]

       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.

       -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-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.  The size of the symbol is printed, rather
	   than the value.

       -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.

SEE ALSO    [Toc]    [Back]

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

COPYRIGHT    [Toc]    [Back]

       Copyright (c) 1991, 92, 93, 94, 95, 96, 97, 98, 99,  2000,  2001,  2002
       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".



3rd Berkeley Distribution	  2002-04-18				 NM(1)
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