P_CANSEE(9)

🌸 NAME 🌸

okay so bestie, this is p_cansee — straight from the Kernel Developer's Manual, section P_CANSEE(9) — and it's literally the function that determines visibility of a process. Like, can this thread even see that process? 👀✨ We're getting into it.

🎀 SYNOPSIS 🎀

#include <sys/proc.h>

int
p_cansee(struct thread *td, struct proc *p);

🦋 DESCRIPTION 🦋

So p_cansee() determines if a given process p is visible to the thread td. And the whole notion of “visibility” here? Read it as “awareness of existence” — like, does td even know p exists? 💖

This function explicitly allows a thread to always see its own process, even with pending credentials changes (see ucred(9) for that whole situation). Otherwise, it simply defers to cr_cansee(9). No cap. 💅

🌈 RETURN VALUES 🌈

p_cansee() returns 0 if the process denoted by p is visible by thread td, or ESRCH otherwise. That's the whole vibe check, bestie. ✨

💀 ERRORS 💀

• [ESRCH] — Thread td is not part of process p and cannot see it as determined by cr_cansee(9). 😭

🫶 SEE ALSO 🫶

• cr_cansee(9)
• p_candebug(9)
• ucred(9)

and that's the page, bestie 💖 this little icon is from Debian, dated August 18, 2023 — P_CANSEE(9) foreverrrr 🎀✨