IF_INDEXTONAME(3POSIX)

💖 IF_INDEXTONAME 💖

okay bestie, welcome to the POSIX Programmer's Manual ✨ this one's IF_INDEXTONAME(3POSIX) and she's a whole vibe.

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🌸 PROLOG 🌸

okay so first things first, this manual page is part of the POSIX Programmer's Manual, periodt. but listen — the Linux implementation of this interface may differ, so if you're on Linux you lowkey gotta go consult the corresponding Linux manual page for the deets on Linux behavior. or, plot twist, the interface might not even be implemented on Linux at all 💀 so don't come for me if it's not there.

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✨ NAME ✨

if_indextoname — map a network interface index to its corresponding name 🦋

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🎀 SYNOPSIS 🎀

#include <net/if.h>

char *if_indextoname(unsigned ifindex, char *ifname);

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💅 DESCRIPTION 💅

okay so the if_indextoname() function shall map an interface index to its corresponding name. it's giving translator, but for interfaces 💖

when this function is called, ifname shall point to a buffer of at least {IF_NAMESIZE} bytes. no cap. and the function shall place in this buffer the name of the interface with index ifindex. that's it, that's the whole job, and she ate 👑

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⭐ RETURN VALUE ⭐

if ifindex is an interface index, then the function shall return the value supplied in ifname, which points to a buffer now containing the interface name 🥰 iconic behavior.

otherwise? the function shall return a null pointer and set errno to indicate the error 😭 so check that errno bestie, she's trying to tell you something.

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🔥 ERRORS 🔥

the if_indextoname() function shall fail if:

• ENXIO — the interface does not exist. yeah. she's just not there. ghosted you fr fr 👻

the following sections are informative.

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🌈 EXAMPLES 🌈

none. (i know, i know, we were all hoping for a little demo. not today 🫶)

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🦋 APPLICATION USAGE 🦋

none. (she's mysterious like that ✨)

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💜 RATIONALE 💜

none. (no explanation era, we respect it)

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🧚 FUTURE DIRECTIONS 🧚

none. (the future is unwritten, bestie 💫)

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👑 SEE ALSO 👑

• getsockopt()
• if_freenameindex()
• if_nameindex()
• if_nametoindex()
• setsockopt()

and also the Base Definitions volume of POSIX.1‐2017, <net_if.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, you're officially educated on if_indextoname 💅

this lil masterpiece came to you courtesy of IEEE/The Open Group, 2017, filed under IF_INDEXTONAME(3POSIX) — stay slay, stay mapped, and may your errno always be ENXIO-free 🌸💖✨