issei_cl_read(9)

📦 version 7.3.1, in nixpkgs unstable

💅 issei_cl_read — kernel API manual, bestie edition ✨

okay so real talk, this is from the Kernel API Manual, section 9 (that's the kernel-space girlies only club 🎀), and the star of the show is issei_cl_read(9). she's a little function with one job and she does it. let's get into it 🫶

🌸 NAME 🌸

issei_cl_read — literally reads data from a queue into the buffer you hand her 💖

✨ SYNOPSIS ✨

ssize_t issei_cl_read (struct issei_host_client *cl , u8 **buf , size_t
buf_size );

that's the whole vibe check right there. three args, one ssize_t coming back atcha 😌

🦋 ARGUMENTS 🦋

  • cl — the host client. your main character, the one holding the data 🫶
  • buf — the buffer where the data goes to live. storage unit for your bytes 💅
  • buf_size — how big that buffer is. size matters, ngl 🔥

🧚 DESCRIPTION 🧚

so what she actually does: she tries to take a data buffer from the client and return it to the caller. that's it, that's the whole plot 😭

and here's the important part, bestie, listen up 👑 — the caller receives ownership of the data buffer. it's yours now. you take it home, you take care of it. no cap, that transfer of ownership is the whole point 💀

⭐ RETURN ⭐

  • read data size on success — slay, here's your byte count 💖
  • <0 on error — something went wrong, it's giving flop, check it 🙈

🌈 SEE ALSO 🌈

kernel file ./drivers/misc/issei/host_client.c and honestly her whole friend group:

iykyk, they all live together in that one file 💜

mwah, that's a wrap ✨ this little number ships out of ./drivers/misc/issei, dated October 2026 — periodt, go read some queues bestie 🎀💅

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