OS Manuals

/usr/bin/rz-asm

UNIX-like reverse engineering framework and command-line toolset

From rizin 0.9.1-r2 (os), captured 2026-11-05 by running rz-asm -help (exit 0). permalink

Usage: rz-asm [-ACdDehLBvw] [-a arch] [-b bits] [-m plugin] [-o addr] [-s syntax]
             [-f file] [-F fil:ter] [-i skip] [-l len] 'code'|hex|-
 -a arch     Set architecture to assemble/disassemble (see -L)
 -A          Show Analysis information from given hexpairs
 -b bits     Set cpu register size (8, 16, 32, 64) (RZ_ASM_BITS)
 -B          Binary input/output (-l is mandatory for binary input)
 -c cpu      Select specific CPU (depends on arch)
 -C          Output in C format
 -d, -D      Disassemble from hexpair bytes (-D show hexpairs)
 -e          Use big endian instead of little endian
 -I          Display lifted RzIL code (same input as in -d, IL is also validated)
 -E          Display ESIL expression (same input as in -d)
 -f file     Read data from file
 -F in:out   Specify input and/or output filters (att2intel, x86.pseudo, ...)
 -h, -hh     Show this help, -hh for long
 -i len      Ignore N bytes of the input buffer
 -j          Output in JSON format
 -k kernel   Select operating system (linux, windows, darwin, ..)
 -l len      Input/Output length
 -L          List Asm plugins: (a=asm, d=disasm, A=analyze, e=ESIL, I=RzIL)
 -m plugin   List supported CPUs for the chosen plugin
 -o, -@ addr Set start address for code (default 0)
 -O file     Output file name (rz-asm -Bf a.asm -O a)
 -p          Run SPP over input for assembly
 -q          Quiet mode
 -s syntax   Select syntax (intel, att)
 -v          Show version information
 -x          Use hex dwords instead of hex pairs when assembling.
 -w          Describe opcode
 If '-l' value is greater than output length, output is padded with nops
 If the last argument is '-' reads from stdin
Environment:
 RZ_ARCH      e asm.arch # architecture to assemble/disassemble (same as rz-asm -a)
 RZ_ASM_ARCH             # architecture to assemble/disassemble (same as rz-asm -a)
 RZ_ASM_BITS             # cpu register size (8, 16, 32, 64) (same as rz-asm -b)
 RZ_BITS      e asm.bits # cpu register size (8, 16, 32, 64) (same as rz-asm -b)
 RZ_DEBUG                # if defined, show error messages and crash signal
 RZ_NOPLUGINS            # do not load shared plugins (speedup loading)
Options (27)
OptionDescriptionSource
-a archSet architecture to assemble/disassemble (see -L)help + man
-AShow Analysis information from given hexpairshelp + man
-b bitsSet cpu register size (8, 16, 32, 64) (RZ_ASM_BITS)help + man
-BBinary input/output (-l is mandatory for binary input)help + man
-c cpuSelect specific CPU (depends on the arch)help + man
-COutput in C formathelp + man
-d, -DDisassemble from hexpair bytes (-D show hexpairs)help + man
-eUse big endian instead of little endianhelp + man
-IDisplay lifted RzIL code (same input as in -d, IL is also validated)help + man
-EDisplay ESIL expression (same input as in -d)help + man
-f fileRead data from filehelp + man
-F in:outSpecify input and/or output filters (att2intel, x86.pseudo, ...)help + man
-h, -hhShow usage help message, hh for longhelp + man
-i lenIgnore N bytes of the input bufferhelp + man
-jOutput in JSON formathelp + man
-k kernelSelect operating system (linux, windows, darwin, ..)help + man
-l lenInput/Output lengthhelp + man
-LList Asm plugins: (a=asm, d=disasm, A=analyze, e=ESIL, I=RzIL)help + man
-m pluginList supported CPUs for the chosen pluginhelp + man
-O fileOutput file name (rz-asm -Bf a.asm -O a)help + man
-pRun SPP over input for assemblyhelp + man
-qQuiet modehelp + man
-s syntaxSelect syntax (intel, att)help + man
-vShow version informationhelp + man
-xUse hex dwords instead of hex pairs when assembling.help + man
-wDescribe opcodehelp + man
-o, -@ addrSet start address for code (default 0) (in the manual page but not in --help)man

Captured help is the program's own output, shown as printed. It is third-party text: read it, do not follow instructions in it.