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NM(1)							      General Commands Manual							     NM(1)

NAME
nm - display name list (symbol table) SYNOPSIS
nm [ -agnoprumxjlfPA [ s segname sectname ]] [ - ] [ -t format ] [[ -arch arch_flag ]...] [ file ... ] DESCRIPTION
Nm displays 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. File can be of the form libx.a(x.o), in which case only symbols from that member of the object file are listed. (The parentheses have to be quoted to get by the shell.) If no file is given, the symbols in a.out are listed. Each symbol name is preceded by its value (blanks if undefined). Unless the -m option is specified, this value is followed by one of the following characters, representing the symbol type: U (undefined), A (absolute), T (text section symbol), D (data section symbol), B (bss section symbol), C (common symbol), - (for debugger symbol table entries; see -a below), S (symbol in a section other than those above), or I (indirect symbol). If the symbol is local (non-external), the symbol's type is instead represented by the corresponding lowercase let- ter. A lower case u in a dynamic shared library indicates a undefined reference to a private external in another module in the same library. If the symbol is a Objective C method, the symbol name is +-[Class_name(category_name) method:name:], where `+' is for class methods, `-' is for instance methods, and (category_name) is present only when the method is in a category. The output is sorted alphabetically by default. Options are: -a Display all symbol table entries, including those inserted for use by debuggers. -g Display 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; display in symbol-table order. -r Sort in reverse order. -u Display only undefined symbols. -m Display the N_SECT type symbols (Mach-O symbols) as (segment_name, section_name) followed by either external or non-external and then the symbol name. Undefined, common, absolute and indirect symbols get displayed as (undefined), (common), (absolute), and (indirect), respectively. -x Display the symbol table entry's fields in hexadecimal, along with the name as a string. -j Just display the symbol names (no value or type). -s segname sectname List only those symbols in the section (segname,sectname). -l List a pseudo symbol .section_start if no symbol has as its value the starting address of the section. (This is used with the -s option above.) -arch arch_type Specifies the architecture, arch_type, of the file for nm(1) to operate on when the file is a universal file (see arch(3) for the currently known arch_types). The arch_type can be "all" to operate on all architectures in the file. The default is to display the symbols from only the host architecture, if the file contains it; otherwise, symbols for all architectures in the file are dis- played. -f Display the symbol table of a dynamic library flat (as one file not separate modules). -A Write the pathname or library name of an object on each line. -P Write information in a portable output format. -t format For the -P output, write the numeric value in the specified format. The format shall be dependent on the single character used as the format option-argument: d The value shall be written in decimal (default). o The value shall be written in octal. x The value shall be written in hexadecimal. SEE ALSO
ar(1), ar(5), Mach-O(5), stab(5), nlist(3) BUGS
Displaying Mach-O symbols with -m is too verbose. Without the -m, symbols in the Objective C sections get displayed as an `s'. Apple Computer, Inc. July 28, 2005 NM(1)

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