MQTTAsync_connectData(3)

💖 MQTTAsync_connectData 💖

okay bestie, so this is from the Library Functions Manual, and it's the MQTTAsync_connectData(3) page — yes the whole page is literally just this one struct and every single field in it, and honestly? iconic. let's get into it 🫶

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✨ NAME ✨

MQTTAsync_connectData — the struct that holds your connect options, no cap 🌸

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✨ SYNOPSIS ✨

#include <MQTTAsync.h>

🌈 Data Fields 🌈

char struct_id [4]
int struct_version
const char * username
struct {
   int len
   const void * data
} binarypwd

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✨ Detailed Description ✨

so basically, these are the connect options that you can update before an automatic reconnect. that's the whole vibe. 💅

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✨ Field Documentation ✨

🌟 char struct_id[4]

the eyecatcher for this structure, bestie. it will be MQCD. it's giving "hello, i am definitely this struct" energy ✨

🌟 int struct_version

the version number of this structure. it will be 0. periodt. 🎀

🌟 const char* username

okay so, MQTT servers that support the MQTT v3.1 protocol provide authentication and authorisation by user name and password — and this is the user name parameter, right here. 🦋

set data to NULL to remove it. and if you wanna change it? allocate new storage with ::MQTTAsync_allocate — the library will then free it later for you. she's self-cleaning, we love that 💖

🌟 int len

binary password length 🍓

🌟 const void* data

binary password data 🌸

🌟 struct { ... } binarypwd

the password parameter of the MQTT authentication, bestie. 🔥

set data to NULL to remove it. and to change it, allocate new storage with ::MQTTAsync_allocate — this will then be free later by the library. same deal as username, she's got her own lil cleanup crew 💅

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✨ Author ✨

generated automatically by Doxygen for Paho Asynchronous MQTT C Client Library from the source code. not a human, just doxygen doing doxygen things 🤖✨

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🫶 that's the whole page bestie, every field accounted for, no skips, no shortcuts, we ate and left no crumbs 💅

and that's a wrap from the Paho Asynchronous MQTT C... crew, dated Tue Jun 2 2026 00:00:00 — same MQTTAsync_connectData(3) you came in with, just a whole lot cuter. bye babes! 💖🌈👑