| .\" Copyright (c) Bruno Haible <haible@clisp.cons.org> |
| .\" and Copyright (C) 2014 Michael Kerrisk <mtk.manpages@gmail.com> |
| .\" |
| .\" %%%LICENSE_START(GPLv2+_DOC_ONEPARA) |
| .\" This is free documentation; you can redistribute it and/or |
| .\" modify it under the terms of the GNU General Public License as |
| .\" published by the Free Software Foundation; either version 2 of |
| .\" the License, or (at your option) any later version. |
| .\" %%%LICENSE_END |
| .\" |
| .\" References consulted: |
| .\" GNU glibc-2 source code and manual |
| .\" Dinkumware C library reference http://www.dinkumware.com/ |
| .\" OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html |
| .\" ISO/IEC 9899:1999 |
| .\" |
| .TH TOWLOWER 3 2021-03-22 "GNU" "Linux Programmer's Manual" |
| .SH NAME |
| towlower, towlower_l \- convert a wide character to lowercase |
| .SH SYNOPSIS |
| .nf |
| .B #include <wctype.h> |
| .PP |
| .BI "wint_t towlower(wint_t " wc ); |
| .BI "wint_t towlower_l(wint_t " wc ", locale_t " locale ); |
| .fi |
| .PP |
| .RS -4 |
| Feature Test Macro Requirements for glibc (see |
| .BR feature_test_macros (7)): |
| .RE |
| .PP |
| .BR towlower_l (): |
| .nf |
| Since glibc 2.10: |
| _XOPEN_SOURCE >= 700 |
| Before glibc 2.10: |
| _GNU_SOURCE |
| .fi |
| .SH DESCRIPTION |
| The |
| .BR towlower () |
| function is the wide-character equivalent of the |
| .BR tolower (3) |
| function. |
| If |
| .I wc |
| is an uppercase wide character, |
| and there exists a lowercase equivalent in the current locale, |
| it returns the lowercase equivalent of |
| .IR wc . |
| In all other cases, |
| .I wc |
| is returned unchanged. |
| .PP |
| The |
| .BR towlower_l () |
| function performs the same task, |
| but performs the conversion based on the character type information in |
| the locale specified by |
| .IR locale . |
| The behavior of |
| .BR towlower_l () |
| is undefined if |
| .I locale |
| is the special locale object |
| .B LC_GLOBAL_LOCALE |
| (see |
| .BR duplocale (3)) |
| or is not a valid locale object handle. |
| .PP |
| The argument |
| .I wc |
| must be representable as a |
| .I wchar_t |
| and be a valid character in the locale or be the value |
| .BR WEOF . |
| .SH RETURN VALUE |
| If |
| .I wc |
| was convertible to lowercase, |
| .BR towlower () |
| returns its lowercase equivalent; |
| otherwise it returns |
| .IR wc . |
| .SH VERSIONS |
| The |
| .BR towlower_l () |
| function first appeared in glibc 2.3. |
| .SH ATTRIBUTES |
| For an explanation of the terms used in this section, see |
| .BR attributes (7). |
| .ad l |
| .nh |
| .TS |
| allbox; |
| lbx lb lb |
| l l l. |
| Interface Attribute Value |
| T{ |
| .BR towlower () |
| T} Thread safety MT-Safe locale |
| T{ |
| .BR towlower_l () |
| T} Thread safety MT-Safe |
| .TE |
| .hy |
| .ad |
| .sp 1 |
| .SH CONFORMING TO |
| .BR towlower (): |
| C99, POSIX.1-2001 (XSI); |
| present as an XSI extension in POSIX.1-2008, but marked obsolete. |
| .PP |
| .BR towlower_l (): |
| POSIX.1-2008. |
| .SH NOTES |
| The behavior of these functions depends on the |
| .B LC_CTYPE |
| category of the locale. |
| .PP |
| These functions are not very appropriate for dealing with Unicode characters, |
| because Unicode knows about three cases: upper, lower, and title case. |
| .SH SEE ALSO |
| .BR iswlower (3), |
| .BR towctrans (3), |
| .BR towupper (3), |
| .BR locale (7) |
