FPUTWC(3P)

💖 FPUTWC(3P) — POSIX Programmer's Manual 💖

okay bestie, so this is the POSIX Programmer's Manual page for fputwc, and you're gonna want to know one thing up top: the Linux implementation of this interface may differ (so go check the corresponding Linux manual page for the deets on Linux behavior), or the interface might not even be implemented on Linux at all. 🙈 iykyk.

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✨ PROLOG ✨

so basically, 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. no cap, that's the whole prolog. 💅

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🎀 NAME 🎀

fputwc — put a wide-character code on a stream

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🦋 SYNOPSIS 🦋

#include <stdio.h>
#include <wchar.h>

wint_t fputwc(wchar_t wc, FILE *stream);

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🌸 DESCRIPTION 🌸

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.1‐2017 defers to the ISO C standard. (yes queen, defer to the standard, we love a humble king 👑)

So here's the tea: the fputwc() function shall write the character corresponding to the wide-character code wc to the output stream pointed to by stream, at the position indicated by the associated file-position indicator for the stream (if defined), and it advances the indicator appropriately. ✨ If the file cannot support positioning requests, or if the stream was opened with append mode, the character is appended to the output stream.

🚨 if an error occurs while writing the character, the shift state of the output file is left in an undefined state. not undefined like "mystery vibes", undefined like good luck bestie.

The last data modification and last file status change timestamps of the file shall be marked for update between the successful execution of fputwc() and the next successful completion of a call to fflush() or fclose() on the same stream, or a call to exit() or abort(). timestamps stay booked and busy fr fr 🕐

Also: the fputwc() function shall not change the setting of errno if successful. she minds her own business. 💅

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🌈 RETURN VALUE 🌈

Upon successful completion, fputwc() shall return wc. Otherwise, it shall return WEOF, the error indicator for the stream shall be set, and errno shall be set to indicate the error.

so like... success = you get your char back. failure = WEOF + error indicator + errno doing the most. 😭

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💀 ERRORS 💀

The fputwc() function shall fail if either the stream is unbuffered or data in the stream's buffer needs to be written, and:

• EAGAIN — The O_NONBLOCK flag is set for the file descriptor underlying stream and the thread would be delayed in the write operation.
• EBADF — The file descriptor underlying stream is not a valid file descriptor open for writing.
• EFBIG — An attempt was made to write to a file that exceeds the maximum file size or the file size limit of the process.
• EFBIG — The file is a regular file and an attempt was made to write at or beyond the offset maximum associated with the corresponding stream. (yes, EFBIG shows up twice, she's that iconic 💅)
• EILSEQ — The wide-character code wc does not correspond to a valid character.
• EINTR — The write operation was terminated due to the receipt of a signal, and no data was transferred.
• EIO — A physical I/O error has occurred, or the process is a member of a background process group attempting to write to its controlling terminal, TOSTOP is set, the calling thread is not blocking SIGTTOU, the process is not ignoring SIGTTOU, and the process group of the process is orphaned. This error may also be returned under implementation-defined conditions.
• ENOSPC — There was no free space remaining on the device containing the file.
• EPIPE — An attempt is made to write to a pipe or FIFO that is not open for reading by any process. A SIGPIPE signal shall also be sent to the thread.

The fputwc() function may fail if:

• ENOMEM — Insufficient storage space is available.
• ENXIO — A request was made of a nonexistent device, or the request was outside the capabilities of the device.

💡 heads up: the following sections are informative. (aka the lore, not the law 🫶)

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🍓 EXAMPLES 🍓

None.

bestie there is literally nothing here. the examples said "no thoughts, head empty" 🧚

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💜 APPLICATION USAGE 💜

None.

also empty. we stan a minimal queen. 👑

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⭐ RATIONALE ⭐

None.

none again!! the rationale said "i have no explanation, i simply am" 💅

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🧚 FUTURE DIRECTIONS 🧚

None.

nothing coming down the pipeline. the future is a blank page and she's thriving. 🌈

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🔥 SEE ALSO 🔥

• Section 2.5, Standard I/O Streams
• ferror()
• fopen()
• setbuf()
• ulimit()

The Base Definitions volume of POSIX.1‐2017:

• <stdio.h>
• <wchar.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, slayed, no notes 💖✨ this one came courtesy of IEEE/The Open Group, dated 2017 — go forth and put those wide characters on that stream, you absolute main character 🎀🦋