process_vm_rw_core(9)

💖 process_vm_rw_core(9) 💖

okay so bestie, welcome to the Kernel API Manual — this is the process_vm_rw_core(9) page and it's literally the main character of cross-process memory copying. pull up a chair 🎀

---

✨ NAME ✨

process_vm_rw_core — the core of reading/writing pages from a task you specify. like, the core. the blueprint. the blueprint-est. 💅

---

🌸 SYNOPSIS 🌸

ssize_t process_vm_rw_core (pid_t pid , struct iov_iter *iter , const
       struct iovec *rvec , unsigned long riovcnt , unsigned long flags , int
       vm_write );

copy it exactly, no cap, don't be out here retyping it from memory 😭

---

🦋 ARGUMENTS 🦋

• pid — the PID of the process you're reading from / writing to. that's your target bestie, the one whose memory we're vibing with 🫶
• iter — where to copy to/from locally. this is the home side of the operation, the local hangout spot.
• rvec — the iovec array specifying where to copy to/from in the other process. so this one's the remote side, the long-distance-relationship side 💌
• riovcnt — size of the rvec array. yes, you do have to tell it how big the array is. we don't do guessing here.
• flags — currently unused. she's there, she's taking up space in the signature, she's iconic for it 👑
• vm_write — 0 if reading from the other process, 1 if writing to the other process. binary queen, no in-between 🌈

---

⭐ DESCRIPTION ⭐

Returns the number of bytes read/written, or an error code. that's the whole job description and she ate 💀

⚠️ heads up bestie: it may return less bytes than expected if an error occurs during the copying process. so like, don't assume "returned N" means "everything worked perfectly forever" — read the return value, fr fr. partial copies are a real vibe check 😭

---

🔥 SEE ALSO 🔥

• Kernel file ./mm/process_vm_access.c
• process_vm_rw_pages(9)
• process_vm_rw_single_vec(9)
• process_vm_rw(9)

go read the whole friend group, they're all connected, iykyk 🌸

---

and that's the page bestie!! brought to you by the ./mm directory, dated October 2026 — mwah, go copy some pages responsibly 💜✨🎀