LLAPI_LAYOUT_COMP_ID_GET(3)

💖 LLAPI_LAYOUT_COMP_ID_GET — the lustre library functions page, section 3, bestie 💖

okay so real talk, this one lives in section 3 of the Lustre Library Functions manual, and it's literally the chillest little getter you'll ever meet. no cap.

---

✨ NAME ✨

llapi_layout_comp_id_get — get the ID of a layout component. that's it, that's the whole job 🎀

---

🌸 SYNOPSIS 🌸

#include <lustre/lustreapi.h>

int llapi_layout_comp_id_get(const struct llapi_layout *layout,
                             uint32_t *comp_id);

---

🦋 DESCRIPTION 🦋

so what this does is: it hands you back the unique numeric ID comp_id of the currently active component of layout. that's the whole thing. you give it a layout, it tells you which component is the active one, by number. slay.

and here's the part where you gotta pay attention, bestie, because the vibes around this ID are very specific:

• the ID of a component is a unique numeric identifier for that component within the layout of each file. so like, per-file unique. that's the scoping.
• and that's it — no age, no ordering, no relative position, no other semantics are implied by the component ID. the number is not a rank. it's not a timestamp. it's not "this one came first." it's just an ID. do not read into it, i'm begging 🙈
• if a file's layout is modified a large number of times, the component ID may be re-used, but it will still always be unique within a single file's layout. so like... recycled sometimes, but never duplicated inside the same layout. iconic behavior honestly.

---

💅 RETURN VALUES 💅

• Returns 0 on success. yay! 🫶
• Returns -1 if an error occurred, and it sets errno appropriately, because of course it does.

---

💀 ERRORS 💀

• EINVAL — an invalid argument was specified. you gave it something it couldn't work with. it's giving "bestie what is this" 😭

---

🌈 AVAILABILITY 🌈

llapi_layout_comp_id_get() is part of the lustre(7) user application interface library, and it's been there since release 2.10.0. so it's not new, it's just new to you. 🔥

---

👑 SEE ALSO 👑

• llapi_layout_alloc(3)
• llapi_layout_comp_use_id(3)
• llapi_layout_file_open(3)
• llapi_layout(7)
• lustreapi(7)

---

and that's the whole page, periodt. go get your component IDs, they're waiting for you. this was written by the Lustre User API crew, dated 2024-08-27, and honestly? they ate. 💖✨🎀