FPUTWC(3POSIX)

🌸 FPUTWC — put a wide-character code on a stream 💖

okay bestie, welcome to fputwc(3POSIX), from the POSIX Programmer's Manual ✨ this is the vibe:

🫶 PROLOG

So like, this manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ — so go check the corresponding Linux manual page for the deets on Linux behavior, mkay? Or... the interface might not even be implemented on Linux at all 🙈 no cap.

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✨ NAME

fputwc — put a wide-character code on a stream 💅

🎀 SYNOPSIS

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

wint_t fputwc(wchar_t wc, FILE *stream);

🦋 DESCRIPTION

The functionality on this reference page is aligned with the ISO C standard. If anything here conflicts with the ISO C standard, that was not the intention, promise. This volume of POSIX.1‐2017 defers to the ISO C standard, periodt.

So fputwc() 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 that's defined, anyway), and it advances the indicator appropriately. If the file can't support positioning requests, or if the stream was opened with append mode, the character just gets appended to the output stream. And if an error occurs while writing the character? The shift state of the output file is left in an undefined state 😭 yeah. undefined. we don't love that.

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 🗓️

Also! fputwc() shall not change the setting of errno if it's successful. we love a function that minds its own business 💖

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👑 RETURN VALUE

• Upon successful completion, fputwc() shall return wc. slay.
• Otherwise, it shall return WEOF, the error indicator for the stream shall be set, and errno shall be set to indicate the error. not slay. 😭

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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. bestie is not about to wait around 🫠
• EBADF — The file descriptor underlying stream is not a valid file descriptor open for writing. like girl, that's not even a real door 🚪
• 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, that's not a typo, that's just how it is 💅)
• EILSEQ — The wide-character code wc does not correspond to a valid character. it's giving invalid.
• 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. no room, no vibes 💀
• 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. yeah that's a double hit 🚨

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. they're not requirements, they're just along for the ride 🧚

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🌈 EXAMPLES

None. literally nothing. empty. iconic of them honestly.

💜 APPLICATION USAGE

None. also empty. we're just vibing 🦋

⭐ RATIONALE

None. nothing to justify here, bestie.

🎀 FUTURE DIRECTIONS

None. the future is... also none? okay periodt.

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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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okay that's the whole page bestie, you ate 💅✨ brought to you by IEEE/The Open Group, 2017, and the one and only FPUTWC(3POSIX) 🫶🌸