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NM(1) FreeBSD General Commands Manual NM(1)
NAME
nm - display symbolic information in object files
SYNOPSIS
nm [--debug-syms] [--defined-only] [--demangle[=style]] [--dynamic]
[--extern-only] [--help] [--line-numbers] [--no-demangle] [--no-sort]
[--numeric-sort] [--print-armap] [--print-file-name] [--print-size]
[--radix=format] [--reverse-sort] [--size-sort] [--undefined-only]
[--version] [-A] [-B] [-C [style]] [-D] [-P] [-V] [-a] [-e] [-g] [-h]
[-l] [-n] [-o] [-p] [-r] [-S] [-s] [-t format] [-u] [-x] file ...
DESCRIPTION
The nm utility displays symbolic information in the object files,
executables, and object library files named by its arguments. Lack of
symbolic information in an otherwise valid input file, is not considered
to be an error. If no files are specified on the command line, nm will
attempt to read a.out.
The nm utility recognizes the following options:
--debug-syms Display all symbols, including debugger-only symbols.
--defined-only
Display only defined symbols.
--demangle[=style]
Decode (demangle) low-level symbol names into human-
readable names. Supported values for argument style are
`auto', `gnu-v2', `gnu-v3' and `arm.' If argument style is
not specified, it is taken to be `auto'.
--dynamic Only display dynamic symbols. This option is only
meaningful for shared libraries.
--extern-only Only display information about global (external) symbols.
--help Display a help message and exit.
--format=format
Display output in the format specified by argument format.
Supported values for the format argument are `bsd',
`sysv', and `posix'. The default output format is `bsd'.
--line-numbers
Display the filename and line number associated a symbol
using any debugging information present in the input file.
For defined symbols, look up the line number associated
with the address of the symbol. For undefined symbols,
look up the line number associated with a relocation entry
that refers to the symbol. If line number information can
be determined, it is displayed after other symbol
information.
--no-demangle Do not demangle symbol names (default).
--no-sort Do not sort symbols.
--print-file-name
Write the full pathname or library name of an object on
each line, before the rest of the information for a
symbol. If this option is not specified, nm will only
identify an input file once, before its symbols are
listed.
--print-size Print the size of each symbol instead of its value.
--radix=radix Print numeric values using the specified radix. Supported
values for argument radix are `d' for decimal, `o' for
octal, and `x' for hexadecimal.
--reverse-sort
Reverse the order of the sort.
--size-sort Sort symbols by size instead of alphabetically by name.
--undefined-only
Display only undefined symbols.
--version Display the version identifier for nm and exit.
-A Equivalent to specifying option --print-file-name.
-B Equivalent to specifying option --format=bsd.
-C [style] Equivalent to specifying option --demangle[=style].
-D Equivalent to specifying option --dynamic.
-F format Equivalent to specifying option --format=format.
-P Equivalent to specifying option --format=posix.
-S Equivalent to specifying option --print-size.
-V Equivalent to specifying option --version.
-a Equivalent to specifying option --debug-syms.
-e Only display information for global and static symbols.
-f Produce full output (default).
-g Equivalent to specifying option --extern-only.
-h Equivalent to specifying option --help.
-l Equivalent to specifying option --line-numbers.
-n Equivalent to specifying option --numeric-sort.
-o If POSIX output was specified using the -F posix or -P
options, this option is equivalent to specifying
--radix=`o'. If POSIX output was not specified, this
option acts as a synonym for the --print-file-name option.
-p Equivalent to specifying option --no-sort.
-t radix Equivalent to specifying option --radix=radix.
-u Equivalent to specifying option --undefined-only.
-x Write numeric values in hexadecimal (equivalent to -t x).
OUTPUT FORMAT
The nm utility can present its information in a number of formats,
numeric radices and sort orders. By default nm uses BSD style output, a
hexadecimal radix, without output sorted alphabetically by name and
without demangling of names.
For each symbol listed, nm presents the following information:
o The library or object name, if options -A or --print-file-name were
specified.
o The symbol name.
o The type of the symbol denoted by a single character as below:
A A global, absolute symbol.
B A global "bss" (uninitialized data) symbol.
C A "common" symbol, representing uninitialized data.
D A global symbol naming initialized data.
N A debugger symbol.
R A read-only data symbol.
T A global text symbol.
U An undefined symbol.
V A weak object.
W A weak reference.
a A local absolute symbol.
b A local "bss" (uninitialized data) symbol.
d A local data symbol.
r A local read-only data symbol.
t A local text symbol.
v A weak object that is undefined.
w A weak symbol that is undefined.
? None of the above.
o The value of the symbol.
o The size of the symbol if applicable.
o Line number information, if available and if options -l or
--line-numbers were specified.
EXIT STATUS
The nm utility exits 0 on success, and >0 if an error occurs.
SEE ALSO
ar(1), objdump(1), ranlib(1), elf(3)
AUTHORS
The nm utility and this manual page were written by Hyogeol Lee
<hyogeollee@gmail.com>.
FreeBSD 14.2-RELEASE September 13, 2017 FreeBSD 14.2-RELEASE