QB_MAP_NOTIFY_ADD(3)

💖 qb_map_notify_add — from the libqb Programmer's Manual (section 3) 💖

okay so bestie, welcome to qb_map_notify_add(3) 🌸 this is the libqb girly whose whole job is adding a notifier to the map. that's it. that's the gig. and honestly? she ate. 👑

---

✨ NAME ✨

qb_map_notify_add — Add a notifier to the map.

---

✨ SYNOPSIS ✨

#include <qb/qbmap.h>

int32_t qb_map_notify_add(
    qb_map_t         *m,          /* the map instance */
    /*
     * the key (or prefix) to attach the notification to.
     */
    const char       *key,
    qb_map_notify_fn  fn,         /* the callback */
    int32_t           events,     /* the type of events to register for. */
    void             *user_data   /* a pointer to be passed into the callback*/
);

like look at her. five params. no notes. 💅

---

✨ PARAMS ✨

• m — the map instance 🗺️ the actual map you're attaching this whole situation to.
• key — the key (or prefix) to attach the notification to. yes, or prefix, we'll get to that, hold on 🔑
• fn — the callback. the little function that gets to hear about everything 📞
• events — the type of events to register for. you're picking which drama you want notifications about 👀
• user_data — a pointer to be passed into the callback. your lil emotional support pointer, hand-delivered straight to fn 🫶

---

✨ DESCRIPTION ✨

so um. the description section in the original is literally empty. nothing. void. a whole blank space 💀 not me pointing it out but here we are — the vibes are immaculate and the prose is nonexistent. the NAME and PARAMS are doing all the heavy lifting, periodt.

---

✨ RETURN VALUE ✨

• 0 — success 🎀 we love to see it
• -errno — failure 😭 it's giving "something went wrong" and the error code is negative, iykyk

---

✨ NOTE ✨

you can use key prefixes with trie maps. 🌈 so like — trie maps only, bestie. don't try that on the others, they're not built for it.

---

✨ SEE ALSO ✨

the whole friend group showed up, no cap:

• qb_trie_dump(3)
• qb_map_iter_create(3)
• qb_skiplist_create(3)
• qb_map_notify_del(3)
• qb_map_put(3)
• qb_map_count_get(3)
• qb_map_foreach(3)
• qb_map_pref_iter_create(3)
• qb_map_iter_next(3)
• qb_map_get(3)
• qb_map_destroy(3)
• qb_hashtable_create(3)
• qb_map_iter_free(3)
• qb_trie_create(3)
• qb_map_notify_del_2(3)
• qb_map_rm(3)

---

✨ COPYRIGHT ✨

Copyright (C) 2010-2020 Red Hat, Inc. 🫶 protecting the girlies since 2010.

---

okay that's the whole page, you're so welcome 💜 this was libqb's Programmer's Manual, page QB_MAP_NOTIFY_ADD(3), dated 2025-09-16 — and that's the sign-off, mwah, go add a notifier to your map bestie 🦋✨