towupper(3) — Linux manual page

towupper(3)             Library Functions Manual             towupper(3)

NAME         top

       towupper, towupper_l - convert a wide character to uppercase

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #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         top

       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         top

       If wc was convertible to uppercase, towupper() returns its
       uppercase equivalent; otherwise it returns wc.

ATTRIBUTES         top

       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        │
       └───────────────────────────────┴───────────────┴────────────────┘

STANDARDS         top

       towupper()
              C11, POSIX.1-2008 (XSI).

       towupper_l()
              POSIX.1-2008.

HISTORY         top

       towupper()
              C99, POSIX.1-2001 (XSI).  Obsolete in POSIX.1-2008 (XSI).

       towupper_l()
              POSIX.1-2008.  glibc 2.3.

NOTES         top

       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         top

       iswupper(3), towctrans(3), towlower(3), locale(7)

Linux man-pages 6.04           2023-03-30                    towupper(3)

Pages that refer to this page: iswupper(3),  toupper(3),  towctrans(3),  towlower(3),  wcscasecmp(3),  wcsncasecmp(3)

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