NNG_AIO_BEGIN(3)

💖 NNG_AIO_BEGIN(3) 💖

okay so bestie, welcome to the nng_aio_begin page from the NNG Reference Manual — this is the one that starts the async I/O party 🎀

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✨ NAME ✨

nng_aio_begin — begin asynchronous I/O operation 💅

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✨ SYNOPSIS ✨

#include <nng/nng.h>

bool nng_aio_begin(nng_aio *aio);

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✨ DESCRIPTION ✨

so like. The nng_aio_begin() function is what the I/O provider calls to be like "hey, I'm about to process this operation, hold my boba" 🧋

The function may return false, which means the aio has been closed by the caller asynchronously 😭 In that case the provider should abandon the operation and do nothing else — not a single thing, no cap, just walk away.

This operation should be called at the start of any I/O operation, and must be called not more than once for a given I/O operation on a given aio. like once. one time. that's the vibe check.

Once this function is called, if true is returned, then the provider MUST guarantee that nng_aio_finish() is called for the aio exactly once, when the operation is complete or canceled. this is the binding contract, periodt ✍️

Note 🫶 This function is only for I/O providers (those actually performing the operation such as HTTP handler functions or transport providers). Ordinary users of the aio should not call this function. ngl if you're just vibing with an aio normally, this is not your moment — stay in your lane bestie 💜

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✨ RETURN VALUES ✨

• true — the operation has been started 🎉
• false — the operation cannot be started 🙈

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✨ ERRORS ✨

None. literally none, zero, nada 🌸

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✨ SEE ALSO ✨

• nng_aio_alloc(3)
• nng_aio_cancel(3)
• nng_aio_defer(3)
• nng_aio_finish(3)
• nng_aio_result(3)
• nng_aio(5)
• nng(7)

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and that's the whole page, bestie!! this came from the NNG Reference Manual, dated 2026-06-30 — go forth and call nng_aio_begin() responsibly 👑✨