IF_NAMEINDEX(3P)

✨ PROLOG ✨

okay bestie, real talk before we get into it 💖 this manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (so like, go check the corresponding Linux manual page for the details on Linux behavior, fr), or honestly the interface may just not be implemented on Linux at all. iykyk.

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🌸 NAME 🌸

if_nameindex — return all network interface names and indexes

like. ALL of them. every single one. no crumbs left behind 💅

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🎀 SYNOPSIS 🎀

#include <net/if.h>

struct if_nameindex *if_nameindex(void);

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🦋 DESCRIPTION 🦋

okay so the if_nameindex() function shall return an array of if_nameindex structures, one structure per interface. literally one per interface, no skipping, no favourites 👑

The end of the array is indicated by a structure with an if_index field of zero and an if_name field of NULL. that's your little "we're done here" marker, bestie — when you see that, stop reading.

Applications should call if_freenameindex() to release the memory that may be dynamically allocated by this function, after they have finished using it. do NOT forget this part — it's giving leak, and not the cute kind 😭

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💖 RETURN VALUE 💖

An array of structures identifying local interfaces. ✨

A null pointer is returned upon an error, with errno set to indicate the error. so if you get NULL back, check errno — it's trying to tell you something.

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💀 ERRORS 💀

The if_nameindex() function may fail if:

• ENOBUFS — Insufficient resources are available to complete the function. basically the system said "bestie i can't, i'm booked and busy" and there was nothing left to give 💀

The following sections are informative.

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🍓 EXAMPLES 🍓

None.

(she's minimal, she's mysterious, she contains multitudes 🧚)

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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_indextoname()
• if_nametoindex()
• setsockopt()

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 thing, bestie 💅 that was IEEE/The Open Group, from 2017, and this page is IF_NAMEINDEX(3P). slay, stay hydrated, free your memory with if_freenameindex(), mwah 💖✨