From 2fd922afed57c9a068c6d877b88d41391bea9721 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Fri, 7 Oct 2022 16:24:01 +0200
Subject: [PATCH] man: recommend strerror_r() over strerror()
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Let's nudge people towards the use of an anonymous buffer like we
do internally.

"errno" → "errnum", to match the man page for strerror, and also to avoid
confusion with the global variable. In general, I think that errno is a
terrible interface and we shouldn't encourage people to use it. Those functions
use errno-style error numbers, which are a different thing.
---
 man/sd-bus-errors.xml   | 2 +-
 man/sd_notify.xml       | 4 ++--
 src/systemd/sd-daemon.h | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/man/sd-bus-errors.xml b/man/sd-bus-errors.xml
index a69efe03f0..4b9c237052 100644
--- a/man/sd-bus-errors.xml
+++ b/man/sd-bus-errors.xml
@@ -268,7 +268,7 @@
       <citerefentry><refentrytitle>sd_bus_error</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
       <citerefentry><refentrytitle>sd_bus_message_set_allow_interactive_authorization</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
       <citerefentry project='man-pages'><refentrytitle>errno</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
-      <citerefentry project='die-net'><refentrytitle>strerror</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+      <citerefentry project='die-net'><refentrytitle>strerror_r</refentrytitle><manvolnum>3</manvolnum></citerefentry>
     </para>
   </refsect1>
 
diff --git a/man/sd_notify.xml b/man/sd_notify.xml
index 31388b9c3d..de402950bb 100644
--- a/man/sd_notify.xml
+++ b/man/sd_notify.xml
@@ -424,8 +424,8 @@
 
       <programlisting>sd_notifyf(0, "STATUS=Failed to start up: %s\n"
         "ERRNO=%i",
-        strerror(errno),
-        errno);</programlisting>
+        strerror_r(errnum, (char[1024]){}, 1024),
+        errnum);</programlisting>
     </example>
 
     <example>
diff --git a/src/systemd/sd-daemon.h b/src/systemd/sd-daemon.h
index 442b0ac604..53a1d7ccfe 100644
--- a/src/systemd/sd-daemon.h
+++ b/src/systemd/sd-daemon.h
@@ -260,8 +260,8 @@ int sd_notify(int unset_environment, const char *state);
 
      sd_notifyf(0, "STATUS=Failed to start up: %s\n"
                    "ERRNO=%i",
-                   strerror(errno),
-                   errno);
+                   strerror_r(errnum, (char[1024]){}, 1024),
+                   errnum);
 
   See sd_notifyf(3) for more information.
 */
-- 
2.25.1