Nico Golde:

[apps/madmutt.git] / doc / devel-notes.txt

diff --git a/doc/devel-notes.txt b/doc/devel-notes.txt
index 3cfcfc9..51b4212 100644 (file)
--- a/doc/devel-notes.txt
+++ b/doc/devel-notes.txt
@@ -178,3 +178,19 @@ similar to [ntg]roff:
    This is used to protect indentations in tables.
 
 Do _not_ use any other SGML or nroff formatting instructions here!
+
+
+String comparison
+-----------------
+
+A word of warning about string comparisons: Since Mutt-ng may run in a
+huge variety of locales, case-insensitive string comparisons and
+case conversions may be dangerous.  For instance, in iso-8859-9,
+tolower('I') is DIFFERENT from 'i' - it's indeed the Turkish dotless
+lowercase i.
+
+For this reason, always use the ascii_* functions defined in ascii.h
+and implemented in ascii.c when comparing or handling strings which
+are defined as us-ascii.  This concerns lots of text-based
+protocols, message header tags, character set names, domain names,
+e-mail addresses, etc.