ICONV_OPEN(3P)

💖 ICONV_OPEN 💖

okay so bestie, welcome to ICONV_OPEN(3P) — she's a whole section 3P situation (that's the POSIX Programmer's Manual, iykyk), and we're gonna get into it together. grab a lil snack. 🍓

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✨ PROLOG ✨

so like, real talk first: this manual page is part of the POSIX Programmer's Manual. but the Linux implementation of this interface? it may differ (consult the corresponding Linux manual page for the details on Linux behavior, bestie). or honestly, the interface may not even be implemented on Linux at all. 🙈 it's giving "check before you commit".

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🌸 NAME 🌸

iconv_open — codeset conversion allocation function. that's her. that's the whole vibe. 💅

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✨ SYNOPSIS ✨

#include <iconv.h>

iconv_t iconv_open(const char *tocode, const char *fromcode);

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🦋 DESCRIPTION 🦋

okay so the way this works: iconv_open() shall return a conversion descriptor that describes a conversion from the codeset specified by the string pointed to by the fromcode argument to the codeset specified by the string pointed to by the tocode argument. from → to. the glow-up pipeline. 👑

for state-dependent encodings, the conversion descriptor shall be in a codeset-dependent initial shift state, ready for immediate use with iconv(). she's prepped and ready, no warm-up needed.

settings of fromcode and tocode and their permitted combinations are implementation-defined. so like, don't @ me about specifics, that's on your system.

a conversion descriptor shall remain valid until it is closed by iconv_close() or an implicit close. no zombie descriptors in this house. 💀

if a file descriptor is used to implement conversion descriptors, the FD_CLOEXEC flag shall be set; see <fcntl.h>.

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🔥 RETURN VALUE 🔥

upon successful completion, iconv_open() shall return a conversion descriptor for use on subsequent calls to iconv(). slay. ✨

otherwise? iconv_open() shall return (iconv_t)-1 and set errno to indicate the error. not the vibe, but that's the deal.

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💜 ERRORS 💜

the iconv_open() function may fail if:

• EMFILE — All file descriptors available to the process are currently open.
• ENFILE — Too many files are currently open in the system.
• ENOMEM — Insufficient storage space is available.
• EINVAL — The conversion specified by fromcode and tocode is not supported by the implementation.

the following sections are informative. (translation: they're the bonus content, not the main quest. 🎀)

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💅 EXAMPLES 💅

None.

(i know. iconic of them to leave us hanging. 🫶)

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🌈 APPLICATION USAGE 🌈

some implementations of iconv_open() use malloc() to allocate space for internal buffer areas. so iconv_open() may fail if there is insufficient storage space to accommodate these buffers. keep that in mind, bestie. 😭

conforming applications must assume that conversion descriptors are not valid after a call to one of the exec functions. like, once you exec, she's gone. gone gone. 💀

application developers should consult the system documentation to determine the supported codesets and their naming schemes. fr fr, go read the docs.

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⭐ RATIONALE ⭐

None.

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🌸 FUTURE DIRECTIONS 🌸

None.

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🧚 SEE ALSO 🧚

• iconv()
• iconv_close()
• The Base Definitions volume of POSIX.1‐2017, <fcntl.h>, <iconv.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!! 🎀 she was brought to you by IEEE/The Open Group, dated 2017, and her manual name is ICONV_OPEN(3P) in case you forgot already (you didn't, you're a main character). now go open some conversion descriptors responsibly. periodt. 💖🦋✨