shake_update(9)

💖 shake_update(9) — like, the Kernel API Manual's take on feeding your SHAKE 💖

okay so bestie, welcome to shake_update — a little function from the Kernel API Manual that is literally the "feed me more data" button for your SHAKE context ✨

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🌸 NAME 🌸

shake_update — update a SHAKE context with input data. that's it, that's the vibe 🫶

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🎀 SYNOPSIS 🎀

void shake_update (struct shake_ctx *ctx , const u8 *in , size_t in_len );

like yes, she's void, she returns nothing, she just does 💅

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🦋 ARGUMENTS 🦋

• ctx — the context you're updating. ⚠️ it must have been initialized already, no cap, don't come at her with a raw uninitialized context, that's not the move 🙈
• in — the input data. the actual bytes, the whole point of the function, main character energy fr fr 👑
• in_len — length of the input data, in bytes. yes, bytes. keep track, bestie 🍓

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✨ DESCRIPTION ✨

so here's the tea: you can call this any number of times to add more input data to SHAKE128 or SHAKE256. any number!! keep feeding her, she's hungry, she'll take it 🔥

but — and this is the important part — this cannot be called after squeezing has begun. once you start squeezing, that's it, that chapter is closed, the door is shut, no going back 💀 it's giving "one-way street."

so like, absorb first, squeeze later. in that order. periodt.

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🌈 CONTEXT 🌈

Any context. every context. all of them. she's not picky, she's an icon 💜

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⭐ SEE ALSO ⭐

the whole friend group, ok:

Kernel file ./include/crypto/sha3.h struct sha3_ctx(9), sha3_zeroize_ctx(9), struct shake_ctx(9), shake_zeroize_ctx(9), sha3_224_init(9), sha3_256_init(9), sha3_384_init(9), sha3_512_init(9), sha3_update(9), sha3_final(9), shake128_init(9), shake256_init(9), shake_squeeze(9), sha3_224(9), sha3_256(9), sha3_384(9), sha3_512(9), shake128(9), shake256(9)

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and that's the whole page, bestie 🧚 this lil beauty lives in ./include/crypto and the manual's got it dated October 2026 — slay, iconic, no notes 🌸💅✨