YASM_OBJFMTS(7)

💖 yasm_objfmts — Yasm Supported Object Formats 💖

okay bestie, so this is the yasm_objfmts(7) page from the Yasm manual — it's the whole rundown of every object format Yasm can spit out. manual name is right there in the title, so no need to scroll for it. let's get into it ✨

🌸 SYNOPSIS 🌸

yasm -f objfmt ...

like, that's the whole vibe. you pick your format, you go. 🎀

✨ DESCRIPTION ✨

so the standard Yasm distribution ships with a bunch of modules for different object formats — and the object format is Yasm's primary output, so this is kind of a big deal.

you select the object format on the yasm(1) command line using the -f objfmt command line option. that's it. that's the switch. 💅

🦋 BIN 🦋

the "bin" object format makes a flat-format, non-relocatable binary file. it's the one you want for producing DOS .COM executables, or for things like boot blocks. ngl it's lowkey minimal: it supports only 3 sections, and those sections get written in a predefined order to the output file. no negotiating. 📦

🎀 COFF 🎀

COFF is an older relocatable object format used on older Unix and compatible systems — and also, more recently, on the DJGPP development system for DOS. vintage vibes, still showing up to the party. 🕰️

🙈 DBG 🙈

the "dbg" object format is not a "real" object format — bestie, it's not even pretending. what it actually does is create an output file that simply describes:

• the sequence of calls made to it by Yasm
• the final object and symbol table information

...all in a human-readable text format. and yeah, in a normal object format all of that would get processed into that format's particular binary representation instead. so this one is not intended for real use — it's for debugging Yasm's internals. it's giving backstage pass, not main character. 🫶

💜 ELF 💜

the ELF object format really comes in three flavors:

• "elf32" — for 32-bit targets
• "elf64" — for 64-bit targets
• "elfx32" — for x32 targets

ELF is a standard object format in common use on modern Unix and compatible systems (e.g. Linux, FreeBSD). and it has complex support for relocatable and shared objects. it's the it-girl of object formats fr fr. 👑

🌈 MACHO 🌈

Mach-O really comes in two flavors:

• "macho32" — for 32-bit targets
• "macho64" — for 64-bit targets

Mach-O is used as the object format on MacOS X. important caveat though: as Yasm currently only supports x86 and AMD64 instruction sets, it can only generate Mach-O objects for Intel-based Macs. so if you were hoping for something else, that's a no from the codebase. 💀

🍓 RDF 🍓

the RDOFF2 object format is a simple multi-section format that was originally designed for NASM. it supports segment references but not WRT references — noted, don't try it.

it was designed primarily for simplicity, and it has minimalistic headers for ease of loading and linking. and a complete toolchain — linker, librarian, and loader — is distributed with NASM. full set, no missing pieces. 🧰

💅 WIN32 💅

the Win32 object format produces object files compatible with Microsoft compilers (such as Visual C++) that target the 32-bit x86 Windows platform. and plot twist: the object format itself is an extended version of COFF. glow-up. ✨

🔥 WIN64 🔥

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 it produces 64-bit objects. same energy, bigger numbers. 🚀

⭐ XDF ⭐

the XDF object format is essentially a simplified version of COFF. it's a multi-section relocatable format that supports 64-bit physical and virtual addresses. understated, but it does the job. 🤝

👀 SEE ALSO 👀

• yasm(1)
• yasm_arch(7)

go read those next, bestie, they're literally right there. 🫶

🌸 AUTHOR 🌸

Peter Johnson <peter@tortall.net>

• Author.

🎀 COPYRIGHT 🎀

Copyright © 2006 Peter Johnson

and that's the whole page!! 💖 this one came from the Yasm manual, dated February 2007, and it lives at page YASM_OBJFMTS(7) — so if you ever need to find it again, that's the address. periodt. 👑✨