Provided by: yasm_0.7.1-0ubuntu2_i386
yasm_objfmts - Yasm Supported Object Formats
yasm -f objfmt ...
The standard Yasm distribution includes a number of modules for
different object formats (Yasm’s primary output).
The object format is selected on the yasm(1) command line by use of the
-f objfmt command line option.
The “bin” object format produces a flat-format, non-relocatable binary
file. It is appropriate for producing DOS .COM executables or things
like boot blocks. It supports only 3 sections and those sections are
written in a predefined order to the output file.
The COFF object format is an older relocatable object format used on
older Unix and compatible systems, and also (more recently) on the
DJGPP development system for DOS.
The “dbg” object format is not a “real” object format; the output file
it creates simply describes the sequence of calls made to it by Yasm
and the final object and symbol table information in a human-readable
text format (that in a normal object format would get processed into
that object format’s particular binary representation). This object
format is not intended for real use, but rather for debugging Yasm’s
The ELF object format really comes in two flavors: “elf32” (for 32-bit
targets) and “elf64” (for 64-bit targets). ELF is a standard object
format in common use on modern Unix and compatible systems (e.g. Linux,
FreeBSD). ELF has complex support for relocatable and shared objects.
The Mach-O object format really comes in two flavors: “macho32” (for
32-bit targets) and “macho64” (for 64-bit targets). Mach-O is used as
the object format on MacOS X. As Yasm currently only supports x86 and
AMD64 instruction sets, it can only generate Mach-O objects for
The RDOFF2 object format is a simple multi-section format originally
designed for NASM. It supports segment references but not WRT
references. It was designed primarily for simplicity and has
minimalistic headers for ease of loading and linking. A complete
toolchain (linker, librarian, and loader) is distributed with NASM.
The Win32 object format produces object files compatible with Microsoft
compilers (such as Visual C++) that target the 32-bit x86 Windows
platform. The object format itself is an extended version of COFF.
The Win64 object format produces object files compatible with Microsoft
compilers that target the 64-bit “x64” Windows platform. This format is
very similar to the win32 object format, but produces 64-bit objects.
The XDF object format is essentially a simplified version of COFF. It’s
a multi-section relocatable format that supports 64-bit physical and
Peter Johnson <email@example.com>
Copyright © 2006 Peter Johnson