seq_put_hex_ll(9)

📦 version 7.3.1, in nixpkgs unstable

✨ seq_put_hex_ll(9) ✨

okay so bestie, this is a page straight out of the Kernel API Manual and it's all about seq_put_hex_ll — the little icon that puts a number in hexadecimal notation 💅 like it's literally the hex glow-up button for your seq_file output.

🌸 SYNOPSIS 🌸

void seq_put_hex_ll (struct seq_file *m , const char *delimiter ,
       unsigned long long v , unsigned int width );

that's the whole vibe: you hand it a buffer, a lil string, a number, and a width, and it does its thing ✨

🎀 ARGUMENTS 🎀

  • m — the seq_file that identifies the buffer where the data should be written 🫶 like, this is where the hex magic lands.
  • delimiter — a string which is printed before the number 🌈 so it's the cute lil intro before the main character (the number) shows up.
  • v — the number 💖 the actual digits we're flexing in hex.
  • width — a minimum field width 📏 so your number never looks underdressed.

👑 DESCRIPTION 👑

okay so the big slay here is this equality:

seq_put_hex_ll(m, "", v, 8) is equal to seq_printf(m, "08llx", v)

literally identical energy, no cap 💯

and here's the tea: this routine is very quick when you show lots of numbers 🔥 like, it's giving performance, it's giving efficiency, it's giving main character speed.

but ngl, in usual cases, it will be better to use seq_printf. It's easier to read 👀 so like, yeah, the fast one is fast, but the readable one is readable — pick your fighter, bestie 💅

lowkey important: this page is saying seq_printf is the usual-case winner because it's easier to read — don't come for me, that's literally what it says 🫶

🦋 SEE ALSO 🦋

Kernel file ./fs/seq_file.c — and the whole squad of seq friends, fr fr:

and that's the whole page, bestie 🎀 this gem lives in ./fs, dated October 2026, and it's filed under seq_put_hex_ll(9) — go forth and hex responsibly 💜✨

📦 where this page comes from