nfsd_read(9)

📦 version 7.3.1, in nixpkgs unstable

💖 nfsd_read(9) 💖

ok so bestie, welcome to nfsd_read — it's from the Kernel API Manual, and it does exactly one thing and does it slay: read data from a file. That's the whole vibe. 🎀

✨ SYNOPSIS ✨

__be32 nfsd_read (struct svc_rqst *rqstp , struct svc_fh *fhp , loff_t
offset , unsigned long *count , u32 *eof );

like, yes, that's the whole signature. yes, the line break is real. no cap. 💅

🌸 ARGUMENTS 🌸

okay let's go through the cast of characters one by one, they all matter:

  • rqstp — the RPC transaction context. think of it as the group chat this whole operation is happening in 🫶
  • fhp — the file handle of the file you're reading from. the main character, honestly 👑
  • offset — starting byte offset. where in the file we're kicking things off. literally just the starting point bestie 📍
  • count — this one's doing double duty and honestly, iconic: IN: the requested number of bytes; OUT: the number of bytes actually read. she comes in with one job and leaves with a different one 💅✨
  • eof — OUT: set non-zero if the operation reached the end of the file. so you know when you've hit the wall 🧱

🦋 DESCRIPTION 🦋

okay so before you even think about calling this, the caller must verify that there's enough space in rqstp.rq_res to perform this operation. like, that's on you, not on me. do your vibe check first ⭐

⚠️ N.B. — After this call fhp needs an fh_put. do NOT forget this part, i'm so serious 😭 it's giving "you broke it, you fix it" energy.

Returns nfs_ok on success, otherwise an nfserr stat value gets returned. that's it, that's the contract 🤝

🌈 SEE ALSO 🌈

okay the friend group is LARGE and i love them all, here we go — from the kernel file ./fs/nfsd/vfs.c:

anyway that's the page 💜 this whole thing lives in ./fs/nfsd, it's part of the Kernel API Manual, and it's dated October 2026 — so mark your calendars bestie, see u then 🗓️✨ mwah 💋

📦 where this page comes from