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macOS man pages
Raw
nm.txt
NM(1) General Commands Manual NM(1)
NAME
nm - display name list (symbol table)
SYNOPSIS
llvm-nm [ -agnoprumxjlPA ] [ - ] [ -t format ] [[ -arch arch_flag ]...] [
file ... ] [ -s segname sectname ]
nm-classic [ -agnoprumxjlfPA [ s segname sectname ]] [ - ] [ -t format ]
[[ -arch arch_flag ]...] [ file ... ]
DESCRIPTION
As of Xcode 8.0 the default nm(1) tool is llvm-nm(1). For the most part
nm(1) and llvm-nm(1) have the same options; notable exceptions include
-f, -s, and -L as described below. This document explains options common
between the two commands as well as some historically relevant options
supported by nm-classic(1). More help on options for llvm-nm(1) is
provided when running it with the --help option.
nm displays the name list (symbol table of nlist structures) of each
object file in the argument list. In some cases, as with an object that
has had strip(1) with its -T option used on the object, that can be
different than the dyld information. For that information use
dyldinfo(1).
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 letter. 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.
-U Don't display 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. Other symbol details are displayed in a
human-friendly manner, such as "[no dead strip]". nm will display
the referenced symbol for indirect symbols and will display the
name of the library expected to provide an undefined symbol. See
nlist(3) and <mach-o/nlist.h> for more information on the nlist
structure.
-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). For
llvm-nm(1) this option must be last on the command line, and after
the files.
-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 displayed.
-f format
For llvm-nm(1) this specifies the output format. Where format can
be bsd, sysv, posix or darwin.
-f For nm-classic(1) this displays the symbol table of a dynamic
library flat (as one file not separate modules). This is obsolete
and not supported with llvm-nm(1).
-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.
-L Display the symbols in the bitcode files in the (__LLVM,__bundle)
section if present instead of the object's symbol table. For
nm-classic(1) this is the default if the object has no symbol
table and an (__LLVM,__bundle) section exists. This option is not
supported by llvm-nm(1) where displaying llvm bitcode symbols is
the default behavior.
SEE ALSO
ar(1), ar(5), Mach-O(5), stab(5), nlist(3), dyldinfo(1)
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, Inc. December 13, 2018 NM(1)
Raw
otool.txt
OTOOL-CLASSIC(1) General Commands Manual OTOOL-CLASSIC(1)
NAME
otool-classic - object file displaying tool
SYNOPSIS
otool-classic [ option ... ] [ file ... ]
DESCRIPTION
The otool-classic command displays specified parts of object files or
libraries. It is the preferred tool for inspecting Mach-O binaries,
especially for binaries that are bad, corrupted, or fuzzed. It is also
useful in situations when inspecting files with new or "bleeding-edge"
Mach-O file format changes.
For historical reasons, the LLVM-based llvm-objdump(1) tool does support
displaying Mach-O information in an "otool-compatibility" mode. For more
information on using llvm-objdump(1) in this way, see the llvm-otool(1)
command-line shim. Note that llvm-objdump(1) is incapable of displaying
information in all Mach-O files.
If the -m option is not used the file arguments may be of the form
libx.a(foo.o), to request information about only that object file and not
the entire library. (Typically this argument must be quoted,
``libx.a(foo.o)'', to get it past the shell.) Otool-classic understands
both Mach-O (Mach object) files and universal file formats.
Otool-classic can display the specified information in either its raw
(numeric) form (without the -v flag), or in a symbolic form using macro
names of constants, etc. (with the -v or -V flag).
At least one of the following options must be specified:
-a Display the archive header, if the file is an archive.
-S Display the contents of the `__.SYMDEF' file, if the file is an
archive.
-f Display the universal headers.
-h Display the Mach header.
-l Display the load commands.
-L Display the names and version numbers of the shared libraries that
the object file uses, as well as the shared library ID if the file
is a shared library.
-D Display just the install name of a shared library. See
install_name_tool(1) for more info.
-s segname sectname
Display the contents of the section (segname,sectname). If the -v
flag is specified, the section is displayed as its type, unless
the type is zero (the section header flags). Also the sections
(__OBJC,__protocol), (__OBJC,__string_object) and
(__OBJC,__runtime_setup) are displayed symbolically if the -v flag
is specified. For unknown section types, if the -V flag is
specified, the contents of the section are displayed in a
canonical hex+ASCII display, where a column of hexadecimal values
print along side a column of ASCII characters.
-t Display the contents of the (__TEXT,__text) section. With the -v
flag, this disassembles the text. With the -V flag, it also
symbolically disassembles the operands.
-x Display the contents of every __text section found in the file.
This is useful when looking at the Mach kernel and other files
with __text sections in more than one segment, or where the __text
section is somewhere other than __TEXT. When used with the -v
flag, this disassembles the text. When used with the -V flag, it
also symbolically disassembles the operands.
-d Display the contents of the (__DATA,__data) section.
-o Display the contents of the __OBJC segment used by the Objective-C
run-time system.
-r Display the relocation entries.
-c Display the argument strings (argv[] and envp[]) from a core file.
-I Display the indirect symbol table.
-T Display the table of contents for a dynamically linked shared
library.
-R Display the reference table of a dynamically linked shared
library.
-M Display the module table of a dynamically linked shared library.
-H Display the two-level namespace hints table.
-G Display the data in code table.
-C Display the linker optimization hints (-v for verbose mode can
also be added).
-P Print the info plist section, (__TEXT,__info_plist), as strings.
-dyld_info
Print bind and rebase information used by dyld to resolve external
references in a final linked binary.
-dyld_opcodes
Print raw dyld bind and rebase opcodes present in a final linked
binary. These opcodes are stored in a region pointed to by
LC_DYLD_INFO* load commands.
-show-latency
When doing disassembly print latency annotations for instructions.
-chained_fixups
Print raw chained fixup data present in a final linked binary
built with chained fixups. The chained fixup data are stored
either in a region pointed to by the LC_DYLD_CHAINED_FIXUPS load
command or in a (__TEXT,__chain_starts) section. This data
includes the fixup chain's starting location on each page by
segment and symbol information for each bind. Use the -dyld_info
option to see the individual links in each chain.
The following options may also be given:
-j When doing disassembly print the opcode bytes of the instructions.
-m The object file names are not assumed to be in the archive(member)
syntax, which allows file names containing parenthesis.
-p name
Used with the -t and -v or -V options to start the disassembly
from symbol name and continue to the end of the (__TEXT,__text)
section. This option can also be used with the -x option to begin
disassembly from symbol name in any segment where a __text section
is found.
-q Use the llvm disassembler when doing disassembly; this is
available for the x86 and arm architectures. This is the default.
-Q Use otool-classic(1)'s disassembler when doing disassembly.
-v Display verbosely (symbolically) when possible.
-V Display the disassembled operands symbolically (this implies the
-v option). This is useful with the -s, -t, and -x options.
-X Don't print leading addresses or headers with disassembly of
sections.
-addr_slide=arg
When disassembling a binary using the -s, -t, or -o options, add
an arbitrary slide to each pointer value when it is displayed.
This is useful for matching otool output with that from a running
process.
-arch arch_type
Specifies the architecture, arch_type, of the file for
otool-classic(1) to operate on when the file is a universal file
(aka a file with multiple architectures). (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 only the host architecture, if the file contains it;
otherwise, all architectures in the file are shown.
-function_offsets
When doing disassembly print the decimal offset from the last
label printed.
-mcpu=arg
When doing disassembly using the llvm disassembler use the cpu
arg.
--version
Print the otool-classic(1) version information.
SEE ALSO
dyld(1), install_name_tool(1), libtool(1), lipo(1), llvm-otool(1), and
vtool(1)
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