From 799261f0f0ada509bb3c82be49a6e55e62590799 Mon Sep 17 00:00:00 2001
From: Josh Triplett <josh@joshtriplett.org>
Date: Fri, 8 Nov 2024 06:49:02 -0800
Subject: [PATCH] Clarify `getppid` documentation: explain how `None` can occur

The `getppid` syscall can never fail, but rustix returns PID 0 as
`None`.
---
 src/process/id.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/process/id.rs b/src/process/id.rs
index 0df14a8c4..16f16b126 100644
--- a/src/process/id.rs
+++ b/src/process/id.rs
@@ -113,6 +113,9 @@ pub fn getpid() -> Pid {
 
 /// `getppid()`—Returns the parent process' ID.
 ///
+/// This will return `None` if the current process has no parent (or no parent accessible in the
+/// current PID namespace), such as if the current process is an init process (PID 1).
+///
 /// # References
 ///  - [POSIX]
 ///  - [Linux]