MONGOC_TOPOLO...EADABLE_SERVER(3)

💅 mongoc_topology_description_has_readable_server — the vibe check for "is anybody home and can I read from them" ✨

okay so bestie, welcome to the libmongoc manual, section 3 🎀 this one is a little function that answers one very important question: can I actually read from somebody right now? 👑

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🌸 SYNOPSIS 🌸

bool
mongoc_topology_description_has_readable_server (
  const mongoc_topology_description_t *td, const mongoc_read_prefs_t *prefs);

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💖 DESCRIPTION 💖

So like, this function determines if the topology has a readable server available 💅 that's the whole plot.

Servers get filtered by the given read preferences — but only if the driver is connected to a replica set 🦋 otherwise the read preferences are literally ignored, no cap.

And the most important part: this function uses the driver's current knowledge of the state of the MongoDB server or servers it is connected to. It does no I/O and it does not block ✨ so it's giving "instant answer, zero waiting, main character energy" — it just tells you what it already knows, periodt.

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🎀 PARAMETERS 🎀

• td — a mongoc_topology_description_t 💜 like, the topology description itself, the thing you're asking about.
• read_prefs — a mongoc_read_prefs_t, or NULL for default read preferences 🌸 (NULL is totally fine, it'll use the defaults, iykyk).

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⭐ RETURNS ⭐

True if there is a known server matching prefs 👑 that's it, that's the answer.

🫶 remember: it's the known server — this is a vibe check on the driver's existing knowledge, not a fresh probe of the network, so no I/O happens and nothing blocks 😭

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👀 SEE ALSO:

Introduction to Application Performance Monitoring

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💀 AUTHOR

MongoDB, Inc

🌈 COPYRIGHT

2009-present, MongoDB, Inc.

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and that's the whole page, bestie 🍓 mwah 💋 — this little gem is from libmongoc 2.5.6, dated Oct 09, 2026 🧚‍♀️ go forth and check your readable servers 💜✨