[Previous] [Contents] [Index] [Next]

nm

List symbols from object files (POSIX)

Syntax:

nm [ -a ]  [ -g ]
   [ -B ]  [ -C ] [ -D ]
   [ -s ]  [ -A | -o ]
   [ -n | -v ]  [ -p ]
   [ -r ]  [ --size-sort ] [ -u ]
   [ -t radix ] [ -P ]
   [ --target=bfdname ] [ -f format ]
   [ --defined-only ] [-l ]
   [ --no-demangle ] [ -V ]  [ --help ]  
   [ objfile... ]

Options:

-A
-o
Precede each symbol by the name of the input file (or archive element) in which it was found, rather than identify the input file once only, before all of its symbols.
-a
Display all symbols, even debugger-only symbols; normally these aren't listed.
-B
The same as -f bsd (for compatibility with the MIPS nm).
-C
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.
-D
Display the dynamic symbols rather than the normal symbols. This is meaningful only 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; you can use either upper- or lowercase.
-g
Display only external symbols.
-l
("el") 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 that refers to the symbol. If line number information can be found, print it after the other symbol information.
-n
-v
Sort symbols numerically by their addresses, rather than alphabetically by their names.
-p
Don't bother to sort the symbols in any order; print them in the order encountered.
-P
Use the POSIX.2 standard output format instead of the default format. Equivalent to -f posix.
-r
Reverse the order of the sort (whether numeric or alphabetic); let the last come first.
-s
When listing symbols from archive members, include the index: a mapping (stored in the archive by ar) of which modules contain definitions for which names.
-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.
-u
Display only undefined symbols (those external to each object file).
-V
Show the version number of nm and exit.

GNU extensions

--defined-only
Display only defined symbols for each object file.
--help
Show a summary of the options to nm and exit.
--no-demangle
Don't demangle low-level symbol names. This is the default.
--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. The size of the symbol is printed, rather than the value.
--target=bfdname
Specify an object code format other than your system's default format. For more information, see "Target Selection" in the appendix Selecting the Target System.

Description:

The nm utility lists the symbols from the specified object files. If no object files are listed as arguments, nm assumes a.out.

For each symbol, nm shows:

Author:

GNU

See also:

ar


[Previous] [Contents] [Index] [Next]