DISKMAP(4)

💖 DISKMAP(4) 💖

okay so bestie, this is a section 4 manpage from the Kernel Interfaces Manual — yeah, kernel stuff, very main character energy 👑

---

✨ NAME ✨

diskmap — the disklabel UID mapping interface 🎀

🌸 SYNOPSIS 🌸

#include <sys/dkio.h>

🦋 DESCRIPTION 🦋

okay so the diskmap driver is literally the ultimate wingman for userland applications 🫶 — it gives them a way to map a disklabel UID to an actual device and open that device in one atomic operation. one and done, no cap. it pulls this off via the DIOCMAP ioctl(2) command ✨

and like, why is that useful? because sometimes a disk shows up to the operating system under different device names and it's giving chaos 😭 being able to use a disklabel UID is a whole lifesaver in those situations. for example:

• plugging USB keys into differently configured systems — think sd0 or sd1 🙈
• swapping between IDE and AHCI on a disk controller — wd0 or sd0 💀

the way that the device names may change but the operating system is still able to identify the disk by its UID? iconic. periodt. 👑

🍓 FILES 🍓

• /dev/diskmap — the diskmap device 💅

🌈 SEE ALSO 🌈

• ioctl(2)
• disklabel(8)

⭐ HISTORY ⭐

the diskmap driver first appeared in OpenBSD 4.8 🧚 — a whole era, honestly.

💜 AUTHORS 💜

the diskmap driver was written by Joel Sing 🔥

---

and that's the whole vibe check, bestie — this page is from the Debian packaging, dated September 10, 2015, so go forth and map those UIDs 💖✨🎀