IF_INDEXTONAME(3P)

💖 IF_INDEXTONAME(3P) 💖

okay bestie, so this one's from the POSIX Programmer's Manual ✨ — that's the manual name, it's giving official, it's giving standards-body royalty 👑

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🌸 PROLOG 🌸

okay so real talk before we even start: this page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ — like, consult the corresponding Linux manual page for the deets on Linux behavior, bestie, don't come for me 🙈. And it's also possible the interface may not be implemented on Linux at all. vibe check your platform first, fr fr 💅

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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 🎀

So if_indextoname() shall map an interface index to its corresponding name. That's the whole job, and it eats 💅.

When this function is called, ifname shall point to a buffer of at least {IF_NAMESIZE} bytes. Like, at least, bestie — do not come in here with a tiny little baby buffer, that's not the move 😭.

The function shall place in this buffer the name of the interface with index ifindex. So you hand it a number, it hands you back a name, iconic behavior honestly 👑

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🔥 RETURN VALUE 🔥

If ifindex is an interface index, then the function shall return the value supplied in ifname — which now points to a buffer containing the interface name ✨ (yes, the same pointer you passed in, she's just full of name now).

Otherwise? The function shall return a null pointer and set errno to indicate the error. so like. check that pointer. please. 🙏

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💀 ERRORS 💀

The if_indextoname() function shall fail if:

• ENXIO — the interface does not exist. it's not there. it said "never heard of her" 💀

The following sections are informative. (translation: cute but not binding, they're the bonus content 🎁)

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🌈 EXAMPLES 🌈

None.

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🫶 APPLICATION USAGE 🫶

None.

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🧚 RATIONALE 🧚

None.

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⭐ FUTURE DIRECTIONS ⭐

None.

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👑 SEE ALSO 👑

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

The Base Definitions volume of POSIX.1‐2017, <net_if.h> — iykyk 📚

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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, we ate and left no crumbs 🍓✨ this was brought to you by IEEE/The Open Group, dated 2017 — mwah, periodt 💅💖