File 0166-Document-restrictions-on-node-names.patch of Package erlang

From aeadf52ff7313ebe0a0a9d2ca66eced6818d9d4c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=BD=D0=B0=D0=B1?= <nabijaczleweli@nabijaczleweli.xyz>
Date: Fri, 12 Dec 2025 19:57:28 +0100
Subject: [PATCH] Document restrictions on node names

lib/kernel/src/net_kernel.erl:
  valid_name_head(Head) ->
      {ok, MP} = re:compile("^[0-9A-Za-z_\\-]+$", [unicode]),
          case re:run(Head, MP) of
              {match, _} ->
                  true;
              nomatch ->
                  false
      end.

Sponsored-by: https://beaverlabs.net
---
 system/doc/reference_manual/distributed.md | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/system/doc/reference_manual/distributed.md b/system/doc/reference_manual/distributed.md
index e126bd3103..13fad7c050 100644
--- a/system/doc/reference_manual/distributed.md
+++ b/system/doc/reference_manual/distributed.md
@@ -51,7 +51,8 @@ the command-line flag [`-name`](`e:erts:erl_cmd.md#name`) (long names) or
 [`-sname`](`e:erts:erl_cmd.md#sname`) (short names).
 
 The format of the node name is an atom `name@host`. `name` is the name given by
-the user. `host` is the full host name if long names are used, or the first part
+the user, and consists of alphanumerics, `-`, `_`, and `\`.
+`host` is the full host name if long names are used, or the first part
 of the host name if short names are used. Function [`node()`](`erlang:node/0`)
 returns the name of the node.
 
-- 
2.51.0