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segment of this file to be mapped

static link-edit symbol table and stab info

thread state information (list of (flavor, [long]) pairs)

unix thread state information (includes a stack) (list of (flavor, [long] pairs)

dynamic link-edit symbol table info

load a dynamically linked shared library (name, timestamp, current version, compatibility version)

dynamically linked shared lib ident (name, timestamp, current version, compatibility version)

load a dynamic linker (name of dynamic linker)

dynamic linker identification (name of dynamic linker)

modules prebound for a dynamically linked shared library (name, list of module indices)

image routines (virtual address of initialization routine, module index where it resides)

sub framework (name)

sub umbrella (name)

sub client (name)

sub library (name)

two-level namespace lookup hints (list of (subimage index, symbol table index) pairs

prebind checksum (checksum)

load a dynamically linked shared library that is allowed to be missing (symbols are weak imported) (name, timestamp, current version, compatibility version)

64-bit segment of this file to mapped

64-bit image routines (virtual address of initialization routine, module index where it resides)

the uuid for an image or its corresponding dsym file (8 element list of bytes)

runpath additions (path)

local of code signature

local of info to split segments

the object file has no undefined references

the object file is the output of an incremental link against a base file and can't be link edited again

the object file is input for the dynamic linker and can't be staticly link edited again

the object file's undefined references are bound by the dynamic linker when loaded.

the file has its dynamic undefined references prebound.

the file has its read-only and read-write segments split

the image is using two-level name space bindings

the executable is forcing all images to use flat name space bindings

this umbrella guarantees no multiple defintions of symbols in its sub-images so the two-level namespace hints can always be used.

do not have dyld notify the prebinding agent about this executable

the binary is not prebound but can have its prebinding redone. only used when MH_PREBOUND is not set.

indicates that this binary binds to all two-level namespace modules of its dependent libraries. only used when MH_PREBINDABLE and MH_TWOLEVEL are both set.

safe to divide up the sections into sub-sections via symbols for dead code stripping

the binary has been canonicalized via the unprebind operation

the final linked image contains external weak symbols

the final linked image uses weak symbols

When this bit is set, all stacks in the task will be given stack execution privilege. Only used in MH_EXECUTE filetypes.

When this bit is set, the binary declares it is safe for use in processes with uid zero

When this bit is set, the binary declares it is safe for use in processes when issetugid() is true

When this bit is set on a dylib, the static linker does not need to examine dependent dylibs to see if any are re-exported

When this bit is set, the OS will load the main executable at a random address. Only used in MH_EXECUTE filetypes.

read permission

write permission

execute permission

The file contents for this segment is for the high part of the VM space, the low part is zero filled (for stacks in core files).

This segment has nothing that was relocated in it and nothing relocated to it, that is it may be safely replaced without relocation.

regular section

zero fill on demand section

section with only literal C strings

section with only 4 byte literals

section with only 8 byte literals

section with only pointers to literals

section with only non-lazy symbol pointers

section with only lazy symbol pointers

section with only symbol stubs, bte size of stub in the reserved2 field

section with only function pointers for initialization

section with only function pointers for termination

section contains symbols that are to be coalesced

zero fill on demand section (that can be larger than 4 gigabytes)

section with only pairs of function pointers for interposing

section with only 16 byte literals

section contains DTrace Object Format

section with only lazy symbol pointers to lazy loaded dylibs

section contains only true machine instructions

setion contains coalesced symbols that are not to be in a ranlib table of contents

ok to strip static symbols in this section in files with the MH_DYLDLINK flag

no dead stripping

blocks are live if they reference live blocks

used with i386 code stubs written on by dyld

a debug section

section contains soem machine instructions

section has external relocation entries

section has local relocation entries

undefined symbol, n_sect is 0

absolute symbol, does not need relocation, n_sect is 0

symbol is defined in section n_sect

symbol is undefined and the image is using a prebound value for the symbol, n_sect is 0

symbol is defined to be the same as another symbol. n_value is a string table offset indicating the name of that symbol

stab global symbol: name,,0,type,0

stab procedure name (f77 kludge): name,,0,0,0

stab procedure: name,,n_sect,linenumber,address

stab static symbol: name,,n_sect,type,address

stab .lcomm symbol: name,,n_sect,type,address

stab begin nsect sym: 0,,n_sect,0,address

stab emitted with gcc2_compiled and in gcc source

stab register sym: name,,0,type,register

stab src line: 0,,n_sect,linenumber,address

stab end nsect sym: 0,,n_sect,0,address

stab structure elt: name,,0,type,struct_offset

stab source file name: name,,n_sect,0,address

stab object file name: name,,0,0,st_mtime

stab local sym: name,,0,type,offset

stab include file beginning: name,,0,0,sum

stab #included file name: name,,n_sect,0,address

stab compiler parameters: name,,0,0,0

stab compiler version: name,,0,0,0

stab compiler -O level: name,,0,0,0

stab parameter: name,,0,type,offset

stab include file end: name,,0,0,0

stab alternate entry: name,,n_sect,linenumber,address

stab left bracket: 0,,0,nesting level,address

stab deleted include file: name,,0,0,sum

stab right bracket: 0,,0,nesting level,address

stab begin common: name,,0,0,0

stab end common: name,,n_sect,0,0

stab end common (local name): 0,,n_sect,0,address

stab second stab entry with length information

stab global pascal symbol: name,,0,subtype,line

reference to an external non-lazy symbol

reference to an external lazy symbol

symbol is defined in this module

symbol is defined in this module and visible only to modules within this shared library

reference to an external non-lazy symbol and visible only to modules within this shared library

reference to an external lazy symbol and visible only to modules within this shared library

set for all symbols referenced by dynamic loader APIs

indicates the symbol is a weak reference, set to 0 if definition cannot be found

indicates the symbol is a weak definition, will be overridden by a strong definition at link-time

for two-level mach-o objects, specifies the index of the library in which this symbol is defined. zero specifies current image.

relocatable object file

demand paged executable file

core file

preloaded executable file

dynamically bound shared library

dynamic link editor

dynamically bound bundle file

shared library stub for static. linking only, no section contents

companion file with only debug. sections