From d07286c7a396c3c427a447473cebc668f873167a Mon Sep 17 00:00:00 2001
From: Wolfgang Bumiller <w.bumiller@proxmox.com>
Date: Wed, 22 Jan 2020 08:56:51 +0100
Subject: [PATCH] sys: doc update

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
---
 proxmox/src/sys/macros.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/proxmox/src/sys/macros.rs b/proxmox/src/sys/macros.rs
index 17caa2b5..af98670c 100644
--- a/proxmox/src/sys/macros.rs
+++ b/proxmox/src/sys/macros.rs
@@ -30,6 +30,9 @@ macro_rules! io_bail {
 #[doc(hidden)]
 /// Non-panicking assertion: shortcut for returning an `io::Error` if the condition is not met.
 /// Essentially: `if !expr { io_bail_last!() }`.
+///
+/// Note that this uses `errno`, care must be taken not to overwrite it with different value as a
+/// side effect.
 #[macro_export]
 macro_rules! io_assert {
     ($value:expr) => {