callback(3)

callback(3) 💖

okay bestie, so this is a page from the Library Functions Manual — it's callback(3), the callback helpers situation, and it's literally all about running your netlink message callbacks. no cap, it's giving very "small file, big power" energy. let's get into it ✨

---

🌸 NAME 🌸

callback — Callback helpers 🎀

like. the helpers. for your callbacks. that's the vibe. 🦋

---

✨ SYNOPSIS ✨

Functions 💅

int mnl_cb_run2 (const void *buf, size_t numbytes, unsigned int seq,
    unsigned int portid, mnl_cb_t cb_data, void *data, const mnl_cb_t
    *cb_ctl_array, unsigned int cb_ctl_array_len)
int mnl_cb_run (const void *buf, size_t numbytes, unsigned int seq,
    unsigned int portid, mnl_cb_t cb_data, void *data)

two functions. two icons. they're sisters fr fr 💜

---

🌈 Detailed Description 🌈

(this part is just vibes, the real tea is below in the function docs 🍓)

---

👑 Function Documentation 👑

int mnl_cb_run (const void * buf, size_t numbytes, unsigned int seq, unsigned int portid, mnl_cb_t cb_data, void * data) 🫶

mnl_cb_run — callback runqueue for netlink messages (simplified version) 😌✨

Parameters

• buf — buffer that contains the netlink messages 📦
• numbytes — number of bytes stored in the buffer 🔢
• seq — sequence number that we expect to receive 🔁
• portid — Netlink PortID that we expect to receive 🛰️
• cb_data — callback handler for data messages 📞
• data — pointer to data that will be passed to the data callback handler 🫴

so this function is like mnl_cb_run2() but it does not let you set the control callback handlers. that's the whole difference bestie, it's the low-maintenance sibling 💅

Your callback may return three possible values:

• MNL_CB_ERROR (<=-1): an error has occurred. Stop callback runqueue. 💀
• MNL_CB_STOP (=0): stop callback runqueue. ✋
• MNL_CB_OK (>=1): no problems has occurred. ✅

This function propagates the callback return value. like, it hands it right back to you, no editing, no notes 🎀

Definition at line 159 of file callback.c. 📍

---

int mnl_cb_run2 (const void * buf, size_t numbytes, unsigned int seq, unsigned int portid, mnl_cb_t cb_data, void * data, const mnl_cb_t * cb_ctl_array, unsigned int cb_ctl_array_len) 🧚

mnl_cb_run2 — callback runqueue for netlink messages 🔥

Parameters

• buf — buffer that contains the netlink messages 📦
• numbytes — number of bytes stored in the buffer 🔢
• seq — sequence number that we expect to receive 🔁
• portid — Netlink PortID that we expect to receive 🛰️
• cb_data — callback handler for data messages 📞
• data — pointer to data that will be passed to the data callback handler 🫴
• cb_ctl_array — array of custom callback handlers from control messages 🎛️
• cb_ctl_array_len — array length of custom control callback handlers 📏

You can set the cb_ctl_array to NULL if you want to use the default control callback handlers — and in that case, the parameter cb_ctl_array_len is not checked. so don't stress about it, it's literally not being read 👀

Your callback may return three possible values:

• MNL_CB_ERROR (<=-1): an error has occurred. Stop callback runqueue. 💀
• MNL_CB_STOP (=0): stop callback runqueue. ✋
• MNL_CB_OK (>=1): no problem has occurred. ✅

This function propagates the callback return value. On error, it returns -1 and errno is explicitly set. 👇

• If the portID is not the expected, errno is set to ESRCH. 😭
• If the sequence number is not the expected, errno is set to EPROTO. 🙈
• If the dump was interrupted, errno is set to EINTR and you should request a new fresh dump again. 🔄✨

Definition at line 130 of file callback.c. 📍

---

🎀 Author 🎀

Generated automatically by Doxygen for libmnl from the source code. 🤖✨ (yes bestie, a robot wrote it, and it ate 💅)

---

and that's the whole page, periodt 💖 this was libmnl, Version 1.0.5, callback(3) — mwah, take care of your callbacks and they'll take care of you 🫶🌸