Commit: runtime(doc): clarify 'fileignorecase' option setting

[Christian Brabandt]

runtime(doc): clarify 'fileignorecase' option setting

Commit: https://github.com/vim/vim/commit/224f8ca769f2f5c8c4f3293e2adf7672418ba2fe
Author: Christian Brabandt <c...@256bit.org>
Date: Mon Sep 22 19:36:37 2025 +0000

runtime(doc): clarify 'fileignorecase' option setting

fixes: https://github.com/vim/vim/issues/18360

Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index e1361d34d..445e925c3 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -3791,7 +3791,13 @@ A jump table for the options with a short description can be found at |Q_op|.
'fileignorecase' 'fic' boolean (default on for systems where case in file
names is normally ignored)
global
- When set case is ignored when using file names and directories.
+ When set, case is ignored when using file and directory names.
+
+ This option is on by default on systems where the filesystem is
+ traditionally case-insensitive (for example MS-Windows and macOS).
+ However, Vim cannot determine at runtime whether a particular
+ filesystem is case-sensitive or case-insensitive.
+
See 'wildignorecase' for only ignoring case when doing completion.

*'filetype'* *'ft'*