mas_insert(9)

📦 version 7.3.1, in nixpkgs unstable

💅 mas_insert(9)

okay so this is mas_insert, from section 9 of the Kernel API Manual (yes, the kernel one — we're fancy now ✨). She's an internal call to insert a value, and honestly? she's a lil diva with a very specific job. let's get into it 🎀

✨ SYNOPSIS ✨

void * mas_insert (struct ma_state *mas , void *entry );

like literally that's the whole signature bestie, two args, one pointer coming back at you 🫶

🌸 ARGUMENTS 🌸

  • mas — the maple state 💅 this is the whole vibe-holder, the state struct you're working inside of
  • entry — the entry to store 🍓 this is the thing you're yeeting into the tree

👑 RETURN 👑

so the return is giving "it depends" energy, and here's the deal:

  • it returns NULL, or
  • it returns the contents that already exist at the requested index otherwise 🔥
⚠️ important caveat bestie, do NOT skip this: you have to check the maple state for error conditions. like, the return value alone is not the whole story — the state holds the tea on whether things went sideways. so check it, fr fr 😭

🦋 SEE ALSO 🦋

okay this list is long and I'm obsessed, everything lives in the kernel file ./lib/maple_tree.c — buckle up:

like I said. iconic. entire extended universe of maple tree functions 🌈

signed, sealed, delivered 🫶 this one came out of ./lib, dated October 2026, and it's filed under mas_insert(9) — periodt 💜

📦 where this page comes from