Linux "nm" Command Line Options and Examples

list symbols from object files

GNU nm lists the symbols from object files objfile...

Usage:

Related Commands

Command Line Options:

--print-file-name

Precede each symbol by the name of the input file (or archive member) in which it was found, rather thanidentifying the input file once only, before all of its symbols.


                            nm --print-file-name ...

--debug-syms

Display all symbols, even debugger-only symbols; normally these are not listed.


                            nm --debug-syms ...

-B

The same as --format=bsd (for compatibility with the MIPS nm).


                            nm -B ...

--demangle[

Decode (demangle) low-level symbol names into user-level names. Besides removing any initial underscoreprepended by the system, this makes C++ function names readable. Different compilers have differentmangling styles. The optional demangling style argument can be used to choose an appropriate demanglingstyle for your compiler.


                            nm --demangle[ ...

--no-demangle

Do not demangle low-level symbol names. This is the default.


                            nm --no-demangle ...

--dynamic

Display the dynamic symbols rather than the normal symbols. This is only meaningful for dynamic objects,such as certain types of shared libraries.


                            nm --dynamic ...

--format

Use the output format format, which can be "bsd", "sysv", or "posix". The default is "bsd". Only thefirst character of format is significant; it can be either upper or lower case.


                            nm --format ...

--extern-only

Display only external symbols.


                            nm --extern-only ...

--help

Show a summary of the options to nm and exit.


                            nm --help ...

--line-numbers

For each symbol, use debugging information to try to find a filename and line number. For a definedsymbol, look for the line number of the address of the symbol. For an undefined symbol, look for the linenumber of a relocation entry which refers to the symbol. If line number information can be found, printit after the other symbol information.


                            nm --line-numbers ...

--inlines

When option -l is active, if the address belongs to a function that was inlined, then this option causesthe source information for all enclosing scopes back to the first non-inlined function to be printed aswell. For example, if "main" inlines "callee1" which inlines "callee2", and address is from "callee2",the source information for "callee1" and "main" will also be printed.


                            nm --inlines ...

--numeric-sort

Sort symbols numerically by their addresses, rather than alphabetically by their names.


                            nm --numeric-sort ...

--no-sort

Do not bother to sort the symbols in any order; print them in the order encountered.


                            nm --no-sort ...

--portability

Use the POSIX.2 standard output format instead of the default format. Equivalent to -f posix.


                            nm --portability ...

--reverse-sort

Reverse the order of the sort (whether numeric or alphabetic); let the last come first.


                            nm --reverse-sort ...

--print-size

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


                            nm --print-size ...

--print-armap

When listing symbols from archive members, include the index: a mapping (stored in the archive by ar orranlib) of which modules contain definitions for which names.


                            nm --print-armap ...

--radix

Use radix as the radix for printing the symbol values. It must be d for decimal, o for octal, or x forhexadecimal.


                            nm --radix ...

--undefined-only

Display only undefined symbols (those external to each object file).


                            nm --undefined-only ...

--version

Show the version number of nm and exit.


                            nm --version ...

--defined-only

Display only defined symbols for each object file.


                            nm --defined-only ...

--plugin

Load the plugin called name to add support for extra target types. This option is only available if thetoolchain has been built with plugin support enabled.If --plugin is not provided, but plugin support has been enabled then nm iterates over the files in${libdir}/bfd-plugins in alphabetic order and the first plugin that claims the object in question is used.Please note that this plugin search directory is not the one used by ld's -plugin option. In order tomake nm use the linker plugin it must be copied into the ${libdir}/bfd-plugins directory. For GCC basedcompilations the linker plugin is called liblto_plugin.so.0.0.0. For Clang based compilations it iscalled LLVMgold.so. The GCC plugin is always backwards compatible with earlier versions, so it issufficient to just copy the newest one.


                            nm --plugin ...

--size-sort

Sort symbols by size. For ELF objects symbol sizes are read from the ELF, for other object types thesymbol sizes are computed as the difference between the value of the symbol and the value of the symbolwith the next higher value. If the "bsd" output format is used the size of the symbol is printed, ratherthan the value, and -S must be used in order both size and value to be printed.


                            nm --size-sort ...

--special-syms

Display symbols which have a target-specific special meaning. These symbols are usually used by thetarget for some special processing and are not normally helpful when included in the normal symbol lists.For example for ARM targets this option would skip the mapping symbols used to mark transitions betweenARM code, THUMB code and data.


                            nm --special-syms ...

--synthetic

Include synthetic symbols in the output. These are special symbols created by the linker for variouspurposes. They are not shown by default since they are not part of the binary's original source code.


                            nm --synthetic ...

--with-symbol-versions

Enables the display of symbol version information if any exists. The version string is displayed as asuffix to the symbol name, preceeded by an @ character. For example foo@VER_1. If the version is thedefault version to be used when resolving unversioned references to the symbol then it is displayed as asuffix preceeded by two @ characters. For example foo@@VER_2.


                            nm --with-symbol-versions ...

--target

Specify an object code format other than your system's default format.@fileRead command-line options from file. The options read are inserted in place of the original @file option.If file does not exist, or cannot be read, then the option will be treated literally, and not removed.Options in file are separated by whitespace. A whitespace character may be included in an option bysurrounding the entire option in either single or double quotes. Any character (including a backslash)may be included by prefixing the character to be included with a backslash. The file may itself containadditional @file options; any such options will be processed recursively.


                            nm --target ...