IP_RECVTOS(2const)

💖 IP_RECVTOS 💖

okay bestie, so this is IP_RECVTOS from the <rainbow>2const</rainbow> corner of the Linux man-pages — a tiny little switch that makes your sockets spill the tea about incoming packets' Type of Service field. yes it's niche. yes it's iconic. let's go 💅

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✨ NAME ✨

IP_RECVTOS — receive IP_TOS control message 🎀

📚 LIBRARY 📚

Standard C library (libc, -lc) — the classic, the blueprint, fr fr.

🦋 SYNOPSIS 🦋

#include <netinet/in.h>  /* Definition of IP* constants */
#include <sys/socket.h>

int setsockopt(int sockfd, IPPROTO_IP, IP_RECVTOS,
               const int *enable, sizeof(int));

like… copy it exactly, don't get cute with it 😭

💜 DESCRIPTION 💜

So here's the vibe: if you enable this, then the IP_TOS(2const) ancillary message gets passed along with incoming packets. obsessed. That message carries a single byte, and that byte specifies the Type of Service / Precedence field of the packet header. one byte. main character energy. 💫

🚩 heads up bestie: this is not supported for SOCK_STREAM sockets. so don't come for me when it doesn't work there, it literally said so.

💀 ERRORS 💀

Not its own little list, nope — it says go read the others:

• See IPPROTO_IP(2const).
• See setsockopt(2).
• See ip(7).

🌸 HISTORY 🌸

Linux 2.2. ancient. a legend. a pioneer. 🫶

⭐ SEE ALSO ⭐

• IPPROTO_IP(2const)
• setsockopt(2)
• ip(7)

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and that's the whole page, no notes 💖 this tea was served up by Linux man-pages 6.20, dated 2025-11-25 — thank u for coming to my ted talk, mwah 😘✨🌷