unwinddump(1)

💖 unwinddump(1) — General Commands Manual, but make it cute 💖

okay bestie, welcome to the unwinddump(1) page from the General Commands Manual. We're about to get into compact unwind information, and honestly it's giving "niche Unix lore that slaps." 💅✨

🌸 NAME 🌸

unwinddump — Displays compact unwind information in an executable. That's the whole name moment, no cap. 🫶

✨ SYNOPSIS ✨

unwinddump [-arch arch-name] file(s)

So yeah, that's -arch arch-name right there in the brackets, and then file(s) — copied exactly, bestie, we do not play games with the synopsis. 🎀

💖 DESCRIPTION 💖

Okay so picture this: when a C++ (or x86_64 Objective-C) exception is thrown, the runtime must unwind the stack looking for some function to catch the exception. Very main-character energy for the stack, honestly. 😭💅

Traditionally, the unwind information is stored in the __TEXT/__eh_frame section of each executable as Dwarf CFI (call frame information). Yes, Dwarf CFI — not a fantasy creature, just call frame information. 🧚✨

Beginning in Mac OS X 10.6, the unwind information is also encoded in the __TEXT/__unwind_info section using a two-level lookup table of compact unwind encodings. The way that's a two-level lookup table? Obsessed. 🔥👑

The unwinddump tool displays the content of the __TEXT/__unwind_info section. That's it, that's the job. Iconic behavior, fr fr. 🌈

🦋 SEE ALSO 🦋

• ld(1)
• dwarfdump(1)

Go give these other manuals a little visit too, iykyk. 💜

Signed, sealed, delivered by Darwin — November 7, 2008. Bye bestie, stay unwound! 💖🎀🦋