pdcs_auto_write(9)

📦 version 7.3.1, in nixpkgs unstable

💅 pdcs_auto_write(9) — the Kernel API Manual, but make it make sense 🎀

okay so bestie, welcome to pdcs_auto_write(9), straight out of the Kernel API Manual ✨ this is the little corner of the kernel that handles your autoboot/search flag modifying and honestly? it's giving "small function, big responsibilities" 👑

✨ NAME ✨

pdcs_auto_write — this function handles autoboot/search flag modifying 💖

like, that's literally the whole job. it writes the flag. it's an icon, it's a legend, it IS the moment 🫶

🌸 SYNOPSIS 🌸

ssize_t pdcs_auto_write (struct kobject *kobj , struct kobj_attribute
*attr , const char *buf , size_t count , int knob );

so the return type is ssize_t (yes girl, a signed size, don't question it 💀), and it takes five whole arguments. five! main character energy fr fr 🌈

🦋 ARGUMENTS 🦋

  • kobj — the kobject used to share data with userspace. this is the little bridge between kernel-land and the userspace girlies, and we respect her for it 💜
  • attr — the kobject attributes. the vibes and metadata of the situation, basically 🎀
  • buf — the input buffer to read from. this is where the actual data hangs out 📥
  • count — the number of bytes to be read. she's keeping track so nobody reads past the end, we love a boundaries queen ✨
  • knob — the PF_AUTOBOOT or PF_AUTOSEARCH flag. so it's one of those two, no cap, those are the options 👑 (note the capital letters, they're literal names of flags, copy them exactly bestie)

🧚 DESCRIPTION 🧚

okay so here's the tea ☕ we will call this function to change the current autoboot flag. that's the whole errand. that's the assignment. and she ate 🔥

and listen — the kernel is not flexible about this one. we expect a precise syntax:

that's it. that's the end of the paragraph. the page literally says "We expect a precise syntax:" and then... nothing 😭 no syntax shown, no example, no nothing. iconic of her honestly 💀 if you need the exact format, go read the source, because this manpage is leaving us on read 🙈

🍓 SEE ALSO 🍓

the whole friend group, in one very long group chat 💬 plus a very specific kernel file:

Kernel file ./drivers/parisc/pdc_stable.c

like, that's twenty-four references, we are THOROUGH 💅

quick vibe check reminder: this page is from ./drivers/parisc in the kernel tree 🐧 go look at the real source before you go poking at autoboot flags, iykyk 🙈

and that's the page bestie!! 🫶 this little writeup lives in ./drivers/parisc and it's dated October 2026 — so mark your calendars, she's from the future ⭐💖 slay, periodt, go read pdcs_auto_read(9) next for the matching read side 🎀

📦 where this page comes from