1NM(1)                        GNU Development Tools                       NM(1)
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NAME

6       nm - list symbols from object files
7

SYNOPSIS

9       nm [-a|--debug-syms]
10          [-g|--extern-only][--plugin name]
11          [-B] [-C|--demangle[=style]] [-D|--dynamic]
12          [-S|--print-size] [-s|--print-armap]
13          [-A|-o|--print-file-name][--special-syms]
14          [-n|-v|--numeric-sort] [-p|--no-sort]
15          [-r|--reverse-sort] [--size-sort] [-u|--undefined-only]
16          [-t radix|--radix=radix] [-P|--portability]
17          [--target=bfdname] [-fformat|--format=format]
18          [--defined-only] [-l|--line-numbers] [--no-demangle]
19          [-V|--version] [-X 32_64] [--help]  [objfile...]
20

DESCRIPTION

22       GNU nm lists the symbols from object files objfile....  If no object
23       files are listed as arguments, nm assumes the file a.out.
24
25       For each symbol, nm shows:
26
27       ·   The symbol value, in the radix selected by options (see below), or
28           hexadecimal by default.
29
30       ·   The symbol type.  At least the following types are used; others
31           are, as well, depending on the object file format.  If lowercase,
32           the symbol is local; if uppercase, the symbol is global (external).
33
34           "A" The symbol's value is absolute, and will not be changed by
35               further linking.
36
37           "B"
38           "b" The symbol is in the uninitialized data section (known as BSS).
39
40           "C" The symbol is common.  Common symbols are uninitialized data.
41               When linking, multiple common symbols may appear with the same
42               name.  If the symbol is defined anywhere, the common symbols
43               are treated as undefined references.
44
45           "D"
46           "d" The symbol is in the initialized data section.
47
48           "G"
49           "g" The symbol is in an initialized data section for small objects.
50               Some object file formats permit more efficient access to small
51               data objects, such as a global int variable as opposed to a
52               large global array.
53
54           "i" For PE format files this indicates that the symbol is in a
55               section specific to the implementation of DLLs.  For ELF format
56               files this indicates that the symbol is an indirect function.
57               This is a GNU extension to the standard set of ELF symbol
58               types.  It indicates a symbol which if referenced by a
59               relocation does not evaluate to its address, but instead must
60               be invoked at runtime.  The runtime execution will then return
61               the value to be used in the relocation.
62
63           "N" The symbol is a debugging symbol.
64
65           "p" The symbols is in a stack unwind section.
66
67           "R"
68           "r" The symbol is in a read only data section.
69
70           "S"
71           "s" The symbol is in an uninitialized data section for small
72               objects.
73
74           "T"
75           "t" The symbol is in the text (code) section.
76
77           "U" The symbol is undefined.
78
79           "u" The symbol is a unique global symbol.  This is a GNU extension
80               to the standard set of ELF symbol bindings.  For such a symbol
81               the dynamic linker will make sure that in the entire process
82               there is just one symbol with this name and type in use.
83
84           "V"
85           "v" The symbol is a weak object.  When a weak defined symbol is
86               linked with a normal defined symbol, the normal defined symbol
87               is used with no error.  When a weak undefined symbol is linked
88               and the symbol is not defined, the value of the weak symbol
89               becomes zero with no error.  On some systems, uppercase
90               indicates that a default value has been specified.
91
92           "W"
93           "w" The symbol is a weak symbol that has not been specifically
94               tagged as a weak object symbol.  When a weak defined symbol is
95               linked with a normal defined symbol, the normal defined symbol
96               is used with no error.  When a weak undefined symbol is linked
97               and the symbol is not defined, the value of the symbol is
98               determined in a system-specific manner without error.  On some
99               systems, uppercase indicates that a default value has been
100               specified.
101
102           "-" The symbol is a stabs symbol in an a.out object file.  In this
103               case, the next values printed are the stabs other field, the
104               stabs desc field, and the stab type.  Stabs symbols are used to
105               hold debugging information.
106
107           "?" The symbol type is unknown, or object file format specific.
108
109       ·   The symbol name.
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OPTIONS

112       The long and short forms of options, shown here as alternatives, are
113       equivalent.
114
115       -A
116       -o
117       --print-file-name
118           Precede each symbol by the name of the input file (or archive
119           member) in which it was found, rather than identifying the input
120           file once only, before all of its symbols.
121
122       -a
123       --debug-syms
124           Display all symbols, even debugger-only symbols; normally these are
125           not listed.
126
127       -B  The same as --format=bsd (for compatibility with the MIPS nm).
128
129       -C
130       --demangle[=style]
131           Decode (demangle) low-level symbol names into user-level names.
132           Besides removing any initial underscore prepended by the system,
133           this makes C++ function names readable. Different compilers have
134           different mangling styles. The optional demangling style argument
135           can be used to choose an appropriate demangling style for your
136           compiler.
137
138       --no-demangle
139           Do not demangle low-level symbol names.  This is the default.
140
141       -D
142       --dynamic
143           Display the dynamic symbols rather than the normal symbols.  This
144           is only meaningful for dynamic objects, such as certain types of
145           shared libraries.
146
147       -f format
148       --format=format
149           Use the output format format, which can be "bsd", "sysv", or
150           "posix".  The default is "bsd".  Only the first character of format
151           is significant; it can be either upper or lower case.
152
153       -g
154       --extern-only
155           Display only external symbols.
156
157       --plugin name
158           Load the plugin called name to add support for extra target types.
159           This option is only available if the toolchain has been built with
160           plugin support enabled.
161
162       -l
163       --line-numbers
164           For each symbol, use debugging information to try to find a
165           filename and line number.  For a defined symbol, look for the line
166           number of the address of the symbol.  For an undefined symbol, look
167           for the line number of a relocation entry which refers to the
168           symbol.  If line number information can be found, print it after
169           the other symbol information.
170
171       -n
172       -v
173       --numeric-sort
174           Sort symbols numerically by their addresses, rather than
175           alphabetically by their names.
176
177       -p
178       --no-sort
179           Do not bother to sort the symbols in any order; print them in the
180           order encountered.
181
182       -P
183       --portability
184           Use the POSIX.2 standard output format instead of the default
185           format.  Equivalent to -f posix.
186
187       -S
188       --print-size
189           Print both value and size of defined symbols for the "bsd" output
190           style.  This option has no effect for object formats that do not
191           record symbol sizes, unless --size-sort is also used in which case
192           a calculated size is displayed.
193
194       -s
195       --print-armap
196           When listing symbols from archive members, include the index: a
197           mapping (stored in the archive by ar or ranlib) of which modules
198           contain definitions for which names.
199
200       -r
201       --reverse-sort
202           Reverse the order of the sort (whether numeric or alphabetic); let
203           the last come first.
204
205       --size-sort
206           Sort symbols by size.  The size is computed as the difference
207           between the value of the symbol and the value of the symbol with
208           the next higher value.  If the "bsd" output format is used the size
209           of the symbol is printed, rather than the value, and -S must be
210           used in order both size and value to be printed.
211
212       --special-syms
213           Display symbols which have a target-specific special meaning.
214           These symbols are usually used by the target for some special
215           processing and are not normally helpful when included included in
216           the normal symbol lists.  For example for ARM targets this option
217           would skip the mapping symbols used to mark transitions between ARM
218           code, THUMB code and data.
219
220       -t radix
221       --radix=radix
222           Use radix as the radix for printing the symbol values.  It must be
223           d for decimal, o for octal, or x for hexadecimal.
224
225       --target=bfdname
226           Specify an object code format other than your system's default
227           format.
228
229       -u
230       --undefined-only
231           Display only undefined symbols (those external to each object
232           file).
233
234       --defined-only
235           Display only defined symbols for each object file.
236
237       -V
238       --version
239           Show the version number of nm and exit.
240
241       -X  This option is ignored for compatibility with the AIX version of
242           nm.  It takes one parameter which must be the string 32_64.  The
243           default mode of AIX nm corresponds to -X 32, which is not supported
244           by GNU nm.
245
246       --help
247           Show a summary of the options to nm and exit.
248
249       @file
250           Read command-line options from file.  The options read are inserted
251           in place of the original @file option.  If file does not exist, or
252           cannot be read, then the option will be treated literally, and not
253           removed.
254
255           Options in file are separated by whitespace.  A whitespace
256           character may be included in an option by surrounding the entire
257           option in either single or double quotes.  Any character (including
258           a backslash) may be included by prefixing the character to be
259           included with a backslash.  The file may itself contain additional
260           @file options; any such options will be processed recursively.
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SEE ALSO

263       ar(1), objdump(1), ranlib(1), and the Info entries for binutils.
264
266       Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
267       2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free
268       Software Foundation, Inc.
269
270       Permission is granted to copy, distribute and/or modify this document
271       under the terms of the GNU Free Documentation License, Version 1.3 or
272       any later version published by the Free Software Foundation; with no
273       Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
274       Texts.  A copy of the license is included in the section entitled "GNU
275       Free Documentation License".
276
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279binutils-2.20                     2009-10-16                             NM(1)
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