VOP_PATHCONF(9)

💫 VOP_PATHCONF(9) 💫

okay so bestie, welcome to the VOP_PATHCONF page — it's a kernel developer's manual entry (section 9, yep, the kernel-functions one) and it's literally all about one thing: getting the POSIX pathconf info for a vnode. it's giving "small function, big responsibility" energy and honestly? we stan. 🎀

---

✨ SYNOPSIS ✨

first things first, the includes — copy them exactly, no ad-libbing:

#include <sys/param.h>
#include <sys/vnode.h>
#include <sys/unistd.h>

int
VOP_PATHCONF(struct vnode *vp, int name, long *retval);

like, the whole vibe is: you hand it a vnode, you tell it what info you want, and it drops the answer into *retval. slay. 💅

---

🌸 DESCRIPTION 🌸

okay so here are the arguments, one by one, no skipping:

• vp — the vnode you want info about. it's the main character here, lowkey.
• name — the type of information you want back. it's a selector, it's picking the vibe.
• retval — the place where the info gets returned. the drop-off spot. 🫶

so when the function runs, the value of name is what decides what comes back. here's the full menu, iykyk:

• _PC_LINK_MAX — the maximum number of links to a file.
• _PC_NAME_MAX — the maximum number of bytes in a file name.
• _PC_PATH_MAX — the maximum number of bytes in a pathname.
• _PC_PIPE_BUF — the maximum number of bytes which will be written atomically to a pipe.
• _PC_CHOWN_RESTRICTED — return 1 if appropriate privileges are required for the chown(2) system call, otherwise 0.
• _PC_NO_TRUNC — return 1 if file names longer than KERN_NAME_MAX are truncated.

periodt. that's the whole list, we didn't leave a single one out. 💖

---

🔒 LOCKS 🔒

important!! the vnode will be locked on entry and it should remain locked on return. do not come in here unlocking things, bestie, that's not the move. 🚫🔓

---

🦋 RETURN VALUES 🦋

so here's how it goes:

• if name is recognized → *retval gets set to the specified value and zero is returned ✨
• otherwise → EINVAL is returned 😭

that's it, that's the whole contract. no cap.

---

👑 SEE ALSO 👑

• pathconf(2)
• vnode(9)

go read those if you want the bigger picture, bestie. 🧚

---

💜 AUTHORS 💜

this manual page was written by Doug Rabson. giving credit where credit is due, love that for him. 🌈

---

and that's a wrap!! this page came from the Debian crew, dated December 31, 2020 — so like, it's a little vintage but it's still iconic. new year's eve manpage, actually kind of a serve. 🍓⭐💀