TOWUPPER(3P)

💖 PROLOG 💖

Okay bestie, real talk before we get into it — this manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (so like, go check the corresponding Linux manual page for the deets on Linux behavior, fr), or honestly the interface might just not be implemented on Linux at all. Not every vibe ships everywhere. 🙈

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✨ NAME ✨

towupper, towupper_l — transliterate lowercase wide-character code to uppercase 🦋

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🎀 SYNOPSIS 🎀

#include <wctype.h>

wint_t towupper(wint_t wc);
wint_t towupper_l(wint_t wc, locale_t locale);

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🌸 DESCRIPTION 🌸

So for towupper(): 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 — like, not on purpose, bestie. This volume of POSIX.1‐2017 defers to the ISO C standard. Periodt.

The towupper() and towupper_l() functions have as a domain a type wint_t, the value of which the application shall ensure is a character representable as a wchar_t, and a wide-character code corresponding to a valid character in the locale used by the function or the value of WEOF. If the argument has any other value, the behavior is undefined. 💀 So like… don't do that.

If the argument of towupper() or towupper_l() represents a lowercase wide-character code, and there exists a corresponding uppercase wide-character code as defined by character type information in the current locale or in the locale represented by locale, respectively (category LC_CTYPE), the result shall be the corresponding uppercase wide-character code. All other arguments in the domain are returned unchanged. Iconic behavior honestly. 👑

The behavior is undefined if the locale argument to towupper_l() is the special locale object LC_GLOBAL_LOCALE or is not a valid locale object handle. Do NOT do this, I'm begging. 😭

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💅 RETURN VALUE 💅

Upon successful completion, the towupper() and towupper_l() functions shall return the uppercase letter corresponding to the argument passed. Otherwise, they shall return the argument unchanged. Slay, straightforward, no notes. ✨

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🫶 ERRORS 🫶

No errors are defined. Like literally none, she's unproblematic. 💜

The following sections are informative.

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🌈 EXAMPLES 🌈

None.

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🧚 APPLICATION USAGE 🧚

None.

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⭐ RATIONALE ⭐

None.

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🔥 FUTURE DIRECTIONS 🔥

None.

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👑 SEE ALSO 👑

• setlocale()
• uselocale()

The Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale, <locale.h>, <wctype.h>

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💖 COPYRIGHT 💖

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. 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 http://www.opengroup.org/unix/online.html .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

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Okay that's the whole page, bestie, you ate it up 💅 — this one's brought to you by the icons over at IEEE/The Open Group, dated 2017, and the manual is TOWUPPER(3P). Go forth and uppercase responsibly. 🎀✨