snd_interval_mulkdiv(9)

🌸 snd_interval_mulkdiv(9) 🌸

okay bestie, welcome to the Kernel API Manual — yes the Kernel API Manual, we're in the big leagues now 💅 this one's a lil' helper from the ALSA interval math corner and it's honestly lowkey iconic for how much it does with so few words ✨

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✨ NAME ✨

snd_interval_mulkdiv — refine the interval value 🎀

like, it takes an interval and makes it more itself. main character energy fr fr.

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🦋 SYNOPSIS 🦋

void snd_interval_mulkdiv (const struct snd_interval *a , unsigned int k
, const struct snd_interval *b , struct snd_interval *c );

no cap, that's the whole signature. void return, four params, we move 🌈

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💖 ARGUMENTS 💖

• a — dividend 1 🍓 (the first thing getting divided, yes there's a second one, stay with me)
• k — dividend 2 (as integer) 🔥 it's a dividend and it's an unsigned int, she contains multitudes
• b — divisor 💀 the one doing the dividing
• c — result ✨ this is where the answer goes, she's the output param and she's serving

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👑 DESCRIPTION 👑

ok so the actual math is literally:

c = a * k / b

that's it. that's the vibe. you multiply a by k, then divide by b, and the answer lands in c 💖

aaaand the return value: Returns non-zero if the value is changed, zero if not changed. 🫶 so like, check it if you care whether anything actually moved. iykyk.

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🌸 SEE ALSO 🌸

bestie there are so many siblings, this family is huge 😭 all of these live in the Kernel file ./sound/core/pcm_lib.c:

• snd_pcm_set_ops(9)
• snd_pcm_set_sync_per_card(9)
• snd_interval_refine(9)
• snd_interval_div(9)
• snd_interval_muldivk(9)
• snd_interval_ratnum(9)
• snd_interval_ratden(9)
• snd_interval_list(9)
• snd_interval_ranges(9)
• snd_pcm_hw_rule_add(9)
• snd_pcm_hw_constraint_mask(9)
• snd_pcm_hw_constraint_mask64(9)
• snd_pcm_hw_constraint_integer(9)
• snd_pcm_hw_constraint_minmax(9)
• snd_pcm_hw_constraint_list(9)
• snd_pcm_hw_constraint_ranges(9)
• snd_pcm_hw_constraint_ratnums(9)
• snd_pcm_hw_constraint_ratdens(9)
• snd_pcm_hw_constraint_msbits(9)
• snd_pcm_hw_constraint_step(9)
• snd_pcm_hw_constraint_pow2(9)
• snd_pcm_hw_rule_noresample(9)
• snd_pcm_hw_param_value(9)
• snd_pcm_hw_param_first(9)
• snd_pcm_hw_param_last(9)
• snd_pcm_hw_params_bits(9)
• snd_pcm_lib_ioctl(9)
• snd_pcm_period_elapsed_under_stream_lock(9)
• snd_pcm_period_elapsed(9)
• snd_pcm_add_chmap_ctls(9)

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ngl if you're reading this at 3am in a kernel tree, drink some water and go to bed after 💜 the intervals will still be there tomorrow.

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and that's the whole page, periodt 🎀 brought to you straight out of ./sound/core, dated October 2026 — catch you in the next manpage, bestie 🧚‍♀️✨