idr_get_next(9)

💖 idr_get_next(9) — like, the Kernel API Manual page, bestie 💖

Ok so this is from the Kernel API Manual and it's genuinely one of those tiny little functions that carries the whole group project, so listen up 🫶

---

✨ NAME ✨

idr_get_next — find the next populated entry. That's it, that's the whole vibe check 💅

---

🌸 SYNOPSIS 🌸

void * idr_get_next (struct idr *idr , int *nextid );

Not me obsessing over how short this signature is 😭 void * out front, two pointers, done. Iconic.

---

🎀 ARGUMENTS 🎀

• idr — your IDR handle. Like, your whole little tree thing. The main character 🌈
• nextid — a pointer to an ID. Yep, a pointer, not the ID itself. She's indirect, she's mysterious 💜

---

🦋 DESCRIPTION 🦋

So here's the tea, bestie: idr_get_next gives you the next populated entry in the tree — the first one whose ID is greater than or equal to the value pointed to by nextid. No cap.

And here's the part everyone forgets 🙈 on exit, nextid gets updated to the ID of the value it actually found. So it writes back to you. Slay.

⭐ IMPORTANT LOOP MECHANICS, FR FR: if you wanna use this in a loop, you — the user — have to increment the value pointed to by nextid yourself. The function is NOT gonna do it for you. It's not that kind of girl. Please don't skip this step, I am begging 😭

---

🔥 SEE ALSO 🔥

Kernel file ./lib/idr.c — she lives there 💖

• idr_alloc_u32(9)
• idr_alloc(9)
• idr_alloc_cyclic(9)
• idr_remove(9)
• idr_find(9)
• idr_for_each(9)
• idr_get_next_ul(9)
• idr_replace(9)
• IDA description(9)
• ida_alloc_range(9)
• ida_find_first_range(9)
• ida_free(9)
• ida_destroy(9)

Like, the whole IDR/IDA friend group showed up to the party 👑 go say hi to all of them, iykyk.

---

And that's the page!! Brought to you out of ./lib, dated October 2026 — yes, the future 💀✨ bye bestie, go populate that tree 🌸🎀🫶