nasm

Netwide Assembler. NASM will currently output flat-form binary files, a.out, COFF and ELF Unix object files, and Microsoft 16-bit DOS and Win32 object files.

Also included is NDISASM, a prototype x86 binary-file disassembler which uses the same instruction table as NASM.

NASM is released under the 2-clause BSD license.

Installed size: 3.67 MB
How to install: sudo apt install nasm

nasm

The Netwide Assembler, a portable 80x86 assembler

root@kali:~# nasm -h
Usage: nasm [-@ response_file] [options...] [--] filename
  Options:
    -v (or --v)    print the NASM version number and exit
    -@ file        response file; one command line option per line
    -h             list command line options and exit (also --help)
    -h -opt        show additional help for option "-opt"
    -h all         show all available command line help
    -h topics      show list of help topics (also -h list)
    -o outfile     write output to outfile
    --keep-all     output files will not be removed even if an error happens
    -Xformat       specify error reporting format (see -h -X)
    -s             redirect messages to stdout
    -Zfile         redirect messages to file
    --info[=lvl]   display optional informational messages
    --debug[=lvl]  display NASM internal debugging messages
    -M...          generate Makefile dependencies (see -h -M)
    -f format      select output file format (see -h -f)
    -g             generate debugging information
    -F format      select a debugging format (see -h -F)
    -gformat       same as -g -F format
    -l listfile    write listing to a list file
    -Lflags...     add information to the list file (see -h -L)
    -Oflags...     select optimization (see -h -O)
    -t             assemble in limited SciTech TASM compatible mode
    -E (or -e)     preprocess only (writes output to stdout by default)
    -a             don't preprocess (assemble only)
    -Ipath         add a pathname to the include file path
    -Pfile         pre-include a file (also --include)
    -Dmacro[=str]  pre-define a macro
    -Umacro        undefine a macro
    -w+x           enable warning x  (see -h -w)(also -Wx)
    -w-x           disable warning x (also -Wno-x)
    -w[+-]error    promote all warnings to errors (also -Werror)
    -w[+-]error=x  promote warning x to errors (also -Werror=x)
    --pragma str   pre-executes a specific %pragma
    --before str   add line (usually a preprocessor statement) before the input
    --bits nn      set bits to nn (equivalent to --before "BITS nn")
    --no-line      ignore %line directives in input
    --gprefix str  prepend the given string to the names of all extern,
                   common and global symbols (also --prefix)
    --gpostfix str append the given string to the names of all extern,
                   common and global symbols (also --postfix)
    --lprefix str  prepend the given string to local symbols
    --lpostfix str append the given string to local symbols
    --reproducible attempt to produce run-to-run identical output
    --limit-X val  set execution limit X (see -h --limit)

ndisasm

The Netwide Disassembler, an 80x86 binary file disassembler

root@kali:~# ndisasm -h
usage: ndisasm [-aihlruvw] [-b bits] [-o origin] [-s sync...]
               [-e bytes] [-k start,bytes] [-p vendor] file
   -a or -i activates auto (intelligent) sync
   -b 16, -b 32 or -b 64 sets the processor mode
   -u same as -b 32
   -l same as -b 64
   -w wide output (avoids continuation lines)
   -h displays this text
   -r or -v displays the version number
   -e skips <bytes> bytes of header
   -k avoids disassembling <bytes> bytes from position <start>
   -p selects the preferred vendor instruction set (intel, amd, cyrix, idt)

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