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NAME
towupper, towupper_l - convert a wide character to uppercase
SYNOPSIS
#include <wctype.h>
wint_t towupper(wint_t wc);
wint_t towupper_l(wint_t wc, locale_t locale);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
towupper_l():
Since glibc 2.10:
_XOPEN_SOURCE >= 700
Before glibc 2.10:
_GNU_SOURCE
DESCRIPTION
The towupper() function is the wide-character equivalent of the toupper(3) function. If wc is a
lowercase wide character, and there exists an uppercase equivalent in the current locale, it returns the
uppercase equivalent of wc. In all other cases, wc is returned unchanged.
The towupper_l() function performs the same task, but performs the conversion based on the character type
information in the locale specified by locale. The behavior of towupper_l() is undefined if locale is
the special locale object LC_GLOBAL_LOCALE (see duplocale(3)) or is not a valid locale object handle.
The argument wc must be representable as a wchar_t and be a valid character in the locale or be the value
WEOF.
RETURN VALUE
If wc was convertible to uppercase, towupper() returns its uppercase equivalent; otherwise it returns wc.
VERSIONS
The towupper_l() function first appeared in glibc 2.3.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
┌──────────────┬───────────────┬────────────────┐
│ Interface │ Attribute │ Value │
├──────────────┼───────────────┼────────────────┤
│ towupper() │ Thread safety │ MT-Safe locale │
├──────────────┼───────────────┼────────────────┤
│ towupper_l() │ Thread safety │ MT-Safe │
└──────────────┴───────────────┴────────────────┘
CONFORMING TO
towupper(): C99, POSIX.1-2001 (XSI); present as an XSI extension in POSIX.1-2008, but marked obsolete.
towupper_l(): POSIX.1-2008.
NOTES
The behavior of these functions depends on the LC_CTYPE category of the locale.
These functions are not very appropriate for dealing with Unicode characters, because Unicode knows about
three cases: upper, lower and title case.
SEE ALSO
iswupper(3), towctrans(3), towlower(3), locale(7)
COLOPHON
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GNU 2017-09-15 TOWUPPER(3)