php.net |  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login

go to bug id or search bugs for

Request #67815 strtolower/upper should be locale unaware for Turkish I
Submitted: 2014-08-09 18:44 UTC Modified: 2014-08-11 18:43 UTC
From: ongun dot kanat at gmail dot com Assigned:
Status: Not a bug Package: Strings related
PHP Version: 5.5.15 OS: Linux
Private report: No CVE-ID: None
View Developer Edit
 [2014-08-09 18:44 UTC] ongun dot kanat at gmail dot com 
Description:
------------
There are many applications written that uses strtoupper/strtolower like phpMyAdmin. The Turkish 'I','i' causes errors in these applications since strtolower and strtoupper rejects the 'I'->'i'/'i'->'I' conversation on systems with locale "tr_TR.UTF-8". The function may be locale unaware.

Test script:
---------------
<?php
header("Content-type:text/plain; charset=UTF-8");
echo strtolower("I") . "\n" . strtoupper("i");

Expected result:
----------------
i
I

Actual result:
--------------
I
i

Patches

Pull Requests

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2014-08-10 07:36 UTC] fa@php.net 
Related bugs: 

https://bugs.php.net/bug.php?id=18556
https://bugs.php.net/bug.php?id=21771
https://bugs.php.net/bug.php?id=18556
https://bugs.php.net/bug.php?id=29955

Maybe there should be a FAQ entry on the wiki?
 [2014-08-11 14:11 UTC] ongun dot kanat at gmail dot com 
I looked the bug below and found that the issue is 12 years old bug!
https://bugs.php.net/bug.php?id=18556
Although it's tagged closed and in the last comment [jpauli at php dot net] said it is fixed, it still exists.
There is a RFC in wiki but it is about mbstring plugin as I see.
https://wiki.php.net/rfc/multibyte_char_handling?s[]=turkish

Maybe the functions strtolower/strtoupper would work for ASCII as default and a locale parameter for other charsets. It will solve the most of the class loading problems in Turkish locale.
 [2014-08-11 18:43 UTC] nikic@php.net
-Status: Open +Status: Not a bug
 [2014-08-11 18:43 UTC] nikic@php.net 
strtolower and strotoupper work according to the current locale. The Turkish locale has that weird behavior, so that's what you get.

The referenced bugs are not referring to strtolower/strtoupper, but to lower-casing used for case-insensitive comparison of function names and other identifiers. That was a bug and was fixed by using a locale-independent lower-casing function.

My general recommendation is to avoid locales and locale-dependent functions, as locales are a fundamentally broken concept.
 [2014-08-11 23:22 UTC] ongun dot kanat at gmail dot com 
I know that it is not a bug. That is the why I opened this issue as "request".

I also know that str* functions work locale dependent and try to avoid them in the applications I code or explicitly setting en_US or tr_TR as parameter in functions. Yet there are lots of software uses str* functions to include its files, to change its mapped arrays' keys with these functions not only for loading class-names. Fixing the strtouppers in every software I download is utterly annoying. There should be a workaround which utilizes a locale-independent strtoupper/lower or another functions. A php.ini setting would be awesome.

To avoid locales I have to change my system configuration and obviously I don't want to change it to en_US.UTF-8 or something else. As [cankoy at ymail dot com] said in https://bugs.php.net/bug.php?id=18556 changing LC_CTYPE or something else does not solve anything.
 
PHP Copyright © 2001-2025 The PHP Group
All rights reserved. 		Last updated: Tue Nov 04 00:00:01 2025 UTC