IF_NAMEINDEX(3POSIX)

📦 version 2017a, in debian bookworm, debian trixie, ubuntu jammy, ubuntu noble, ubuntu resolute, ubuntu stonking

💖 if_nameindex — bestie, let's get ALL the network interface names and indexes ✨

okay so real quick before we dive in — this page is from the POSIX Programmer's Manual, it's section 3POSIX, and the vibe check is this: the Linux implementation of this interface may differ (so go peek at the corresponding Linux manual page for the tea on Linux behavior), or honestly the interface may not be implemented on Linux at all. 🙈 Just so you know what you're walking into.

✨ PROLOG ✨

This manual page is part of the POSIX Programmer's Manual, and everything above about Linux applies, fr fr. Don't come for me if your platform does its own thing. 💅

🌸 NAME 🌸

if_nameindex — return all network interface names and indexes 🦋

🎀 SYNOPSIS 🎀

#include <net/if.h>

struct if_nameindex *if_nameindex(void);

she takes no arguments, she just returns. main character energy honestly. 👑

💜 DESCRIPTION 💜

So here's the deal, bestie: if_nameindex() shall return an array of if_nameindex structures, one structure per interface. That's it, that's the whole job. 💖

The way you know you've hit the end of the array? There's a structure at the end with an if_index field of zero and an if_name field of NULL. That's your little "the end 🎬" marker. Don't walk past it.

And listen — applications should call if_freenameindex() to release the memory that may be dynamically allocated by this function, after they've finished using it. Like, clean up after yourself. Be a good roommate. 🧹✨

⭐ RETURN VALUE ⭐

On success you get an array of structures identifying local interfaces. 🌈

On error? You get a null pointer, and errno is set to tell you what went wrong. 💀

💅 ERRORS 💅

if_nameindex() may fail if:

  • ENOBUFS — Insufficient resources are available to complete the function. 😭 she's tired, she's out of juice, try again later.
The following sections are informative. (translation: the tea is optional reading but we're still reading it, obviously 🍓)

🧚 EXAMPLES 🧚

None. 😌 iconic of her honestly.

🫶 APPLICATION USAGE 🫶

None. 🌸

🌟 RATIONALE 🌟

None. ⭐

🔥 FUTURE DIRECTIONS 🔥

None. 💀

🌈 SEE ALSO 🌈

  • getsockopt()
  • if_freenameindex()
  • if_indextoname()
  • if_nametoindex()
  • setsockopt()

The Base Definitions volume of POSIX.1‐2017, <net_if.h> 👑

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 .

and that's the whole page, bestie!! 🎀 this absolute baddie of a manpage was brought to you by IEEE/The Open Group, dated 2017, filed under IF_NAMEINDEX(3POSIX) — mwah, take care of her, she's iconic 💖✨🦋

📦 where this page comes from