PR_GET_TAGGED_ADDR_CTRL(2const)

✨ PR_GET_TAGGED_ADDR_CTRL 💅

okay bestie, so this is a page from PR_GET_TAGGED_ADDR_CTRL(2const) — like the const-flavored corner of the prctl(2) universe — and it's genuinely such a cute little call. it gets the tagged address mode for the calling thread. that's it. that's the whole job. no cap.

---

🎀 LIBRARY

Standard C library (libc, -lc) — the usual bestie, always there for you 🫶

---

🌸 SYNOPSIS

#include <linux/prctl.h>  /* Definition of PR_* constants */
#include <sys/prctl.h>

int prctl(PR_GET_TAGGED_ADDR_CTRL, 0L, 0L, 0L, 0L);

not me calling prctl() with four whole 0Ls just to ask a question 😭 iconic behavior honestly.

---

💖 DESCRIPTION

so it returns the current tagged address mode for the calling thread. that's it. main character energy: the calling thread, nobody else. ✨

the call hands you back a nonnegative value describing the current tagged address mode, and that value is encoded exactly the same way as the mode argument of PR_SET_TAGGED_ADDR_CTRL(2const). so like, if you already know the setter, you already speak the getter's language. iykyk 💅

---

👑 RETURN VALUE

on success, you get that nonnegative value we were just talking about. slay.

on error, -1 comes back and errno gets set to tell you what went wrong. rude, but informative. 💀

---

🦋 ERRORS

this feature is either disabled or just not supported by your kernel, or somebody went and disabled it via /proc/sys/abi/tagged_addr_disabled. three ways to get ghosted, fr fr. 💔

---

🍓 FILES

• /proc/sys/abi/tagged_addr_disabled

---

⭐ STANDARDS

Linux. and arm64 only — so if you're not on arm64, bestie, this whole thing is not for you. 🙈

---

🌈 HISTORY

Linux 5.4 (arm64). vintage-ish, but make it arm64. 🎀

---

🔥 SEE ALSO

• prctl(2)
• PR_SET_TAGGED_ADDR_CTRL(2const)

and for the deep lore, go read the kernel source file Documentation/arm64/tagged-address-abi.rst. it's giving required reading, ngl. 📚✨

---

lowkey reminder: that whole mode encoding thing matters — the getter speaks the exact same dialect as the setter's mode argument, so always go read PR_SET_TAGGED_ADDR_CTRL(2const) to decode whatever you get back. 🫶

---

okay that's the whole page, bestie, we ate and left no crumbs 💅🍓

this was Linux man-pages 6.20, dated 2026-02-08, for PR_GET_TAGGED_ADDR_CTRL(2const) — mwah, go tag some addresses responsibly 😭💖