Man Pages

nm - phpMan nm - phpMan

Command: man perldoc info search(apropos)  


File: binutils.info,  Node: nm,  Next: objcopy,  Prev: ar,  Up: Top

2 nm
****

     nm [`-a'|`--debug-syms']
        [`-g'|`--extern-only'][`--plugin' NAME]
        [`-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] [`-f'FORMAT|`--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'
    `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.  For more
          details on common symbols, see the discussion of -warn-common
          in *note Linker options: (ld.info)Options.

    `D'
    `d'
          The symbol is in the initialized data section.

    `G'
    `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'
          For PE format files this indicates that the symbol is in a
          section specific to the implementation of DLLs.  For ELF
          format files this indicates that the symbol is an indirect
          function.  This is a GNU extension to the standard set of ELF
          symbol types.  It indicates a symbol which if referenced by a
          relocation does not evaluate to its address, but instead must
          be invoked at runtime.  The runtime execution will then
          return the value to be used in the relocation.

    `N'
          The symbol is a debugging symbol.

    `p'
          The symbols is in a stack unwind section.

    `R'
    `r'
          The symbol is in a read only data section.

    `S'
    `s'
          The symbol is in an uninitialized data section for small
          objects.

    `T'
    `t'
          The symbol is in the text (code) section.

    `U'
          The symbol is undefined.

    `u'
          The symbol is a unique global symbol.  This is a GNU
          extension to the standard set of ELF symbol bindings.  For
          such a symbol the dynamic linker will make sure that in the
          entire process there is just one symbol with this name and
          type in use.

    `V'
    `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.  On some systems,
          uppercase indicates that a default value has been specified.

    `W'
    `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.  For more information,
          see *note Stabs: (stabs.info)Top.

    `?'
          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
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. *Note c++filt::, for more information on demangling.

`--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.

`--plugin NAME'
     Load the plugin called NAME to add support for extra target types.
     This option is only available if the toolchain has been built with
     plugin support enabled.

`-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-size'
     Print both value and size of defined symbols for the `bsd' output
     style.  This option has no effect for object formats that do not
     record symbol sizes, unless `--size-sort' is also used in which
     case a calculated size is displayed.

`-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
     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 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
     format.  *Note Target Selection::, for more information.

`-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.