UMAD_GET_CA_PORTGUIDS(3)

💖 UMAD_GET_CA_PORTGUIDS 💖

okay bestie, welcome to the OpenIB Programmer's Manual page for umad_get_ca_portguids (that's section 3, the library-calls girlies ✨). grab a strawberry 🍓, we're getting port GUIDs.

🌸 NAME 🌸

umad_get_ca_portguids — the one that gets you the InfiniBand device ports GUIDs. yes, plural. multiple. a whole squad of GUIDs. 💅

✨ SYNOPSIS ✨

#include <infiniband/umad.h>

int umad_get_ca_portguids(char *ca_name, __be64 *portguids, int max);

look at her. three little arguments. iconic. no cap. 🎀

🦋 DESCRIPTION 🦋

so here's the tea, fr fr: umad_get_ca_portguids() fills the portguids array with up to max port GUIDs, and those GUIDs belong to the IB device you named in ca_name. 🫶

and if you pass ca_name as NULL? no worries bestie, it just uses the default IB device instead. main character energy, honestly.

okay and important — the portguids argument is an array of max uint64_t entries. so like, that's your buffer, that's your capacity, be responsible with it. 🧚

👑 RETURN VALUE 👑

on success, umad_get_ca_portguids() returns a non-negative value that equals the number of port GUIDs it actually filled. slay. ✅

⚠️ but NOT all the filled entries may be valid, bestie. invalid entries will be 0. so don't just trust every slot, okay?? 💀

for example — and this is the part that trips people up — on a CA node with only one port, this function returns a value of 2. yep, two. not one. the value at index 0 will be invalid, because it's reserved for switches. so the count is the count, not the number of valid entries. iykyk. 😭

on failure, a negative value is returned. that's it, that's the whole vibe check. 🙈

🌈 SEE ALSO 🌈

• umad_get_cas_names(3) — go read that one next, she's the sister page 💜

💐 AUTHORS 💐

• Hal Rosenstock <halr@voltaire.com>
• Dotan Barak <dotanb@mellanox.co.il>

give them their flowers, they wrote this and they ate. 👑

that's the whole page bestie, thanks for reading!! this gem came to you from OpenIB, dated August 8, 2016 🌸 — and yes, it lives at UMAD_GET_CA_PORTGUIDS(3) in case you need to find her again. mwah. 💅✨🦋