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       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 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

           "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
           member)  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

           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
           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.

           Sort   symbols   numerically   by   their  addresses,  rather  than
           alphabetically 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
           format.  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
           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
           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  system’s  default

           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.


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


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       Texts.  A copy of the license is included in the section entitled ‘‘GNU
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