NNG_SUB_OPEN(3)

✨ NNG_SUB_OPEN(3) ✨

okay bestie, welcome to the NNG Reference Manual 💖 this is the page for nng_sub_open and it's literally your backstage pass to making a brand new sub socket. pull up a chair, we're doing this together 🫶

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🌸 NAME 🌸

nng_sub_open — create sub socket ✨

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🎀 SYNOPSIS 🎀

#include <nng/nng.h>
#include <nng/protocol/pubsub0/sub.h>

int nng_sub0_open(nng_socket *s);

int nng_sub0_open_raw(nng_socket *s);

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💅 DESCRIPTION 💅

so like, there's two functions here and they're sisters, not twins, okay?

• nng_sub0_open() — this one makes a sub version 0 socket and hands it back to you at the location that s is pointing at. that's it, that's the whole job 💖
• nng_sub0_open_raw() — same energy, BUT it makes a sub version 0 socket in raw mode and returns it at the spot s points to. raw mode is the unhinged one, iykyk 🔥

ngl, the "at the location pointed to by s" part matters — you're passing a pointer, she's writing the socket into it. no cap. 💅

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🌈 RETURN VALUES 🌈

• returns 0 when it ate and left no crumbs ✅
• returns non-zero otherwise (aka when it did NOT work, sorry bestie 😭)

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💀 ERRORS 💀

here's the vibe check on what can go wrong:

• NNG_ENOMEM — insufficient memory is available 🧠💥 girl is out of RAM, that's it, that's the problem.
• NNG_ENOTSUP — the protocol is not supported 🙈 like... it's just not in the building.

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👑 SEE ALSO 👑

go read these next, they're iconic:

• nng_socket(5)
• nng_pub(7)
• nng_sub(7)
• nng(7)

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okay that's the whole page babe, you're officially a sub socket girly now 🦋 this was the NNG Reference Manual, dated 2026-06-30, and honestly? she ate. periodt 💅✨🎀