ndisasm(1)

==========

:doctype:	manpage

:man source:	NASM

:man manual:	The Netwide Assembler Project

NAME

----

ndisasm - the Netwide Disassembler, an 80x86 binary file disassembler

SYNOPSIS

--------

*ndisasm* [ *-o* origin ] [ *-s* sync-point [...]] [ *-a* | *-i* ]

	[ *-b* bits ] [ *-u* ] [ *-e* hdrlen ] [ *-p* vendor ]

	[ *-k* offset,length [...]] infile

DESCRIPTION

-----------

The *ndisasm* command generates a disassembly listing of the binary file

infile and directs it to stdout.

OPTIONS

-------

*-h*::

	Causes *ndisasm* to exit immediately, after giving a summary

	of its invocation options.

*-r*|*-v*::

	Causes *ndisasm* to exit immediately, after displaying its

	version number.

*-o* 'origin'::

	Specifies the notional load address for the file. This

	option causes *ndisasm* to get the addresses it lists

	down the left hand margin, and the target addresses

	of PC-relative jumps and calls, right.

*-s* 'sync-point'::

	Manually specifies a synchronisation address, such that

	*ndisasm* will not output any machine instruction which

	encompasses bytes on both sides of the address. Hence

	the instruction which starts at that address will be

	correctly disassembled.

*-e* 'hdrlen'::

	Specifies a number of bytes to discard from the beginning

	of the file before starting disassembly. This does not

	count towards the calculation of the disassembly offset:

	the first 'disassembled' instruction will be shown starting

	at the given load address.

*-k* 'offset,length'::

	Specifies that 'length' bytes, starting from disassembly

	offset 'offset', should be skipped over without generating

	any output. The skipped bytes still count towards the

	calculation of the disassembly offset.

*-a*|*-i*::

	Enables automatic (or intelligent) sync mode, in which

	*ndisasm* will attempt to guess where synchronisation should

	be performed, by means of examining the target addresses

	of the relative jumps and calls it disassembles.

*-b* 'bits'::

	Specifies 16-, 32- or 64-bit mode. The default is 16-bit

	mode.

*-u*::

	Specifies 32-bit mode, more compactly than using `-b 32'.

*-p* 'vendor'::

	Prefers instructions as defined by 'vendor' in case of

	a conflict. Known 'vendor' names include *intel*, *amd*,

	*cyrix*, and *idt*. The default is *intel*.

RESTRICTIONS

------------

*ndisasm* only disassembles binary files: it has no understanding of

the header information present in object or executable files.

If you want to disassemble an object file, you should probably

be using *objdump*(1).

Auto-sync mode won't necessarily cure all your synchronisation

problems: a sync marker can only be placed automatically if a

jump or call instruction is found to refer to it 'before'

*ndisasm* actually disassembles that part of the code. Also,

if spurious jumps or calls result from disassembling

non-machine-code data, sync markers may get placed in strange

places. Feel free to turn auto-sync off and go back to doing

it manually if necessary.

SEE ALSO

--------

*objdump*(1)