_TOUPPER(3P)

💖 _TOUPPER(3P) — the POSIX Programmer's Manual era 💖

okay bestie, so before we even get into it: this page is part of the POSIX Programmer's Manual. 🫶 But heads up, the Linux implementation of this interface may be different (so like, go check the corresponding Linux manual page for the deets on Linux behavior), or honestly the interface might not even be implemented on Linux at all. 🙈 Not every glow-up ships everywhere, yk?

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✨ NAME ✨

_toupper — transliterate lowercase characters to uppercase

the way this one has a whole identity as "the lowercase-to-uppercase girlie"... she's giving simple, she's giving focused 💅

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🌸 SYNOPSIS 🌸

#include <ctype.h>

int _toupper(int c);

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🦋 DESCRIPTION 🦋

So _toupper() is a macro, and it shall be equivalent to toupper() — except (and this is the whole plot twist) the application shall ensure that the argument c is a lowercase letter.

That's it. That's the vibe. You bring the lowercase letter, she brings the uppercase energy. ⭐

lowkey important: you are the one responsible for c being lowercase. That's on you, bestie. 👑

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💜 RETURN VALUE 💜

Upon successful completion, _toupper() shall return the uppercase letter corresponding to the argument passed.

like a little glow-up machine, but only for one character 🎀

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🧚 ERRORS 🧚

No errors are defined. ✨

The following sections are informative.

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🍓 EXAMPLES 🍓

None. 😭

not a single example, not even one. she said "figure it out." iconic behavior honestly.

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🌈 APPLICATION USAGE 🌈

Applications should use the toupper() function instead of the obsolescent _toupper() function.

fr fr, _toupper() is giving obsolescent — like she's still cute but she's on her way out. Use toupper(). 💅

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⭐ RATIONALE ⭐

None.

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👑 FUTURE DIRECTIONS 👑

The _toupper() function may be removed in a future version. 💀

she might not make it to the next era. that's the tea. 😭

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🫶 SEE ALSO 🫶

• islower()
• toupper()

The Base Definitions volume of POSIX.1‐2017, Chapter 7, Locale, <ctype.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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and that's the whole page, bestie!! 🎀 this was brought to you by IEEE/The Open Group, 2017 — the _TOUPPER(3P) girlies stay winning, lowercase in, uppercase out, periodt. 💅✨🦋