NAME¶

udcli - CLI tool for quick disassembly of x86 and x86-64 instructions

SYNOPSIS¶

udcli [options] file

DESCRIPTION¶

udcli is a command-line front-end to the Udis86 disassembler library. It reads machine code and prints a disassembled representation of x86 or x86-64 instructions.

OPTIONS¶

-16

Set the disassembly mode to 16 bits.

-32

Set the disassembly mode to 32 bits (default).

-64

Set the disassembly mode to 64 bits.

-intel

Use Intel (NASM-like) syntax for output (default).

-att

Use AT&T (GAS-like) syntax.

-v vendor

Set CPU vendor. vendor may be intel or amd.

-o pc

Set the program counter to pc. Default is 0.

-s n

Skip n bytes before starting disassembly.

-c n

Disassemble only n bytes.

-x

Read input as whitespace-separated hexadecimal byte values.

Example:

0f 01 ae 00

-noff

Do not display instruction offsets.

-nohex

Do not display instruction byte encoding.

-eflags

Display information about EFLAGS usage.

-access

Display operand access information.

-implicit

Display implicit registers used or modified by the instruction.

-h

Display help information.

--version

Display program version.

EXAMPLE¶

Usage example:

echo "65 67 89 87 76 65 54 56 78 89 09 00 90" | udcli -32 -x

Example output:

0000000080000800 656789877665     mov [gs:bx+0x6576], eax
0000000080000806 54               push esp
0000000080000807 56               push esi
0000000080000808 7889             js 0x80000793
000000008000080a 0900             or [eax], eax
000000008000080c 90               nop

AUTHORS¶

This version of Udis86 is based on a fork of the original project by Willem (canihavesomecoffee).

The original Udis86 project was written by Vivek Thampi.