Nm prints the name list (symbol table) of each object file in the argument list. If an argument is an archive, a listing for each object
file in the archive will be produced. If no file is given, the symbols in "a.out" are listed.
Each symbol name is preceded by its value (blanks if undefined) and one of the letters U (undefined), A (absolute), T (text segment sym-
bol), D (data segment symbol), B (bss segment symbol), C (common symbol), or f file name. If the symbol is local (non-external) the type
letter is in lower case. If the file is an overlaid executable, the overlay number is printed after the name. The number is printed if
the symbol is in an overlay or if it is the entry point (in the base segment) for a subroutine in an overlay. The output is sorted alpha-
-g Print only global (external) symbols.
-n Sort numerically rather than alphabetically.
-o Prepend file or archive element name to each output line rather than only once.
-p Don't sort; print in symbol-table order.
-r Sort in reverse order.
-u Print only undefined symbols.