NNG_REQ_OPEN(3)

💖 NAME 💖

nng_req_open — bestie, this is the one that creates a req socket ✨

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🌸 SYNOPSIS 🌸

okay so first you gotta pull in the headers, no cap:

#include <nng/nng.h>
#include <nng/protocol/reqrep0/req.h>

and then the two main character functions:

int nng_req0_open(nng_socket *s);

int nng_req0_open_raw(nng_socket *s);

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🦋 DESCRIPTION 🦋

So like, there's two of them and they're siblings, not twins, ok?

The nng_req0_open() function creates a req version 0 socket and hands it back to you at the location pointed to by s. That's it. That's the whole vibe. 💅

Then there's the feral one: nng_req0_open_raw() creates a req version 0 socket in raw mode and returns it at the location pointed to by s. Same deal, just raw — iykyk.

literally both of them write the socket into s, so make sure s is actually a real nng_socket pointer, bestie, don't play with me 🙈

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⭐ RETURN VALUES ⭐

These functions return 0 on success, and non-zero otherwise. So 0 is the slay, anything else is the 😭.

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💀 ERRORS 💀

• NNG_ENOMEM — there's not enough memory available. She's hungry, she needs RAM, go feed her 🍓
• NNG_ENOTSUP — the protocol is not supported. Not every build ships with every protocol, so this one can absolutely show up and it's not your fault, it's giving build-config energy 🧚

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👑 SEE ALSO 👑

• nng_options(5)
• nng_socket(5)
• nng_rep(7)
• nng_req(7)
• nng(7)

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that's the whole page bestie, go open that socket 🫶✨

this was NNG_REQ_OPEN(3) from the NNG Reference Manual, dated 2026-06-30 💜