_U_DYN_REGISTER(3libunwind)

💖 _U_DYN_REGISTER — bestie's guide to the libunwind manual 💖

okay so. this is _U_dyn_register from 3libunwind, the programming library girlies know and love. it's giving "my code literally did not exist five seconds ago and yet it needs unwind info" energy. let's get into it 🦋

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✨ NAME ✨

_U_dyn_register — register unwind info for dynamically generated code

like. you made code at runtime. it's your baby. now you gotta tell libunwind about it. that's the whole job 💅

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🌸 SYNOPSIS 🌸

#include <libunwind.h>

void _U_dyn_register(unw_dyn_info_t *di);

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🎀 DESCRIPTION 🎀

so the _U_dyn_register() routine registers unwind info for a dynamically generated procedure. yes, dynamically generated. we're not doing compile-time over here, we're doing main character runtime behavior ✨

the procedure's unwind info is described by a structure of type unw_dyn_info_t — and if you don't know what that struct is about, go read libunwind-dynamic(3libunwind), it's literally required reading, iykyk. a pointer to this structure gets passed in argument di.

and now the part that ate: _U_dyn_register() is guaranteed to execute in constant time. no cap. but — and this is important bestie, don't skip it — that guarantee is in the absence of contention from concurrent calls to _U_dyn_register() or _U_dyn_cancel(). so if everybody's calling it at once, all bets are off. understood? good 🫶

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🔥 THREAD AND SIGNAL SAFETY 🔥

• _U_dyn_register() is thread safe ✅
• but it is not safe to use from a signal handler ❌

bestie. do NOT call this from a signal handler. i'm so serious. it's not a vibe, it's undefined-ish behavior territory and you will be sad 😭

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🦋 SEE ALSO 🦋

• libunwind-dynamic(3libunwind)
• _U_dyn_cancel(3libunwind)

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👑 AUTHOR 👑

David Mosberger-Tang

• Email: dmosberger@gmail.com
• WWW: http://www.nongnu.org/libunwind/

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that's the page, bestie, you ate it 💜 and just so you have the receipts: this is the Programming Library manual, dated 29 August 2023, filed under _U_DYN_REGISTER(3libunwind). slay, stay safe, and always cancel what you register 💖✨🎀