Section: POSIX Programmer's Manual (3P)
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
--- transliterate uppercase wide-character code to lowercase
wint_t towlower(wint_t wc);
wint_t towlower_l(wint_t wc, locale_t locale);
The functionality described on this reference page is aligned with the
ISO C standard. Any conflict between the requirements described here and the
ISO C standard is unintentional. This volume of POSIX.1-2008 defers to the ISO C standard.
functions have as a domain a type
the value of which the application shall ensure is a character
representable as a
and a wide-character code corresponding to a valid character in the
current locale or the value of WEOF.
If the argument has any other value, the behavior is undefined.
If the argument of
represents an uppercase wide-character code, and there exists a
corresponding lowercase wide-character code as defined by character
type information in the current locale
or in the locale represented by
the result shall be the corresponding lowercase wide-character code.
All other arguments in the domain are returned unchanged.
The behavior is undefined if the
is the special locale object LC_GLOBAL_LOCALE or is not a valid locale
Upon successful completion, the
functions shall return the lowercase letter corresponding to the
argument passed; otherwise, they shall return the argument unchanged.
No errors are defined.
The following sections are informative.
The Base Definitions volume of POSIX.1-2008,
Chapter 7, Locale,
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, Copyright (C) 2013 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
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