Improve the doc string of 'string-collate-lessp'

* src/fns.c (Fstring_collate_lessp): Clarify that
IGNORE-CASE argument might be ignored when the operating
system does not implement string collation for the
specified locale.  (Bug#59275)

diff --git a/src/fns.c b/src/fns.c
index 035fa12935236cbeb3ac5d7af1c1d9ad717c3fb0..e337c0958d5dfbf76fec0011f6d3e9e826092322 100644 (file)
--- a/src/fns.c
+++ b/src/fns.c
@@ -596,8 +596,9 @@ To emulate Unicode-compliant collation on MS-Windows systems,
 bind `w32-collate-ignore-punctuation' to a non-nil value, since
 the codeset part of the locale cannot be \"UTF-8\" on MS-Windows.
 
-If your system does not support a locale environment, this function
-behaves like `string-lessp'.  */)
+Some operating systems do not implement correct collation (in specific
+locale environments or at all).  Then, this functions falls back to
+case-sensitive `string-lessp' and IGNORE-CASE argument is ignored.  */)
   (Lisp_Object s1, Lisp_Object s2, Lisp_Object locale, Lisp_Object ignore_case)
 {
 #if defined __STDC_ISO_10646__ || defined WINDOWSNT