socket_getifidx(3)

✨ socket_getifidx(3) ✨

okay bestie, this one's from the Library Functions Manual and honestly it's giving "tiny function, big main character energy" 🫶 it lives in libowfat's socket corner and it's about to save your IPv6 life. no cap.

💖 NAME 💖

socket_getifidx — get that interface number, periodt 💅

🌸 SYNTAX 🌸

#include <libowfat/socket.h>

int socket_getifidx(const char* ifname);

like. that's it. that's the whole entrance. iconic.

🦋 DESCRIPTION 🦋

so socket_getifidx returns the interface number for a symbolic network interface name — think stuff like "eth0" on Linux, for example. you hand it the cute little human-readable name, it hands you back the number. matchmaker behaviour fr fr 😭

and here's the part that actually matters: that interface number can be used as the scope_id for IPv6 communications on link-local addresses. so if you're out here doing IPv6 link-local stuff and you're like "which interface tho??" — this is the function. it's the vibe check for your network interface. 🌈

and if something goes wrong? socket_getifidx returns -1, and it sets errno appropriately. so pls, bestie, check your errno. don't just stare at the -1 and move on. 🙈

👑 SEE ALSO 👑

• socket_getifname(3) — the reverse girlie, name from number 💜
• socket_connect6(3) — where your shiny scope_id actually gets put to work 🔥

okay that's the whole page!! this beauty is socket_getifidx(3) from libowfat's socket crew — no version number or date on the footer, it just signs off with its own name, which is honestly such a slay 💅✨ keep it close, bestie, your link-local IPv6 needs her 🎀🦋🌸