snd_pcm_hw_...aint_integer(9)

📦 version 7.3.1, in nixpkgs unstable

👑 snd_pcm_hw_constraint_integer — the Kernel API Manual, bestie edition ✨

okay so this page lives in the Kernel API Manual (section 9, kernel land, very demure, very mindful) and it's about exactly one little function that does exactly one little thing. she's small, she's precise, she's important 🎀

✨ NAME ✨

snd_pcm_hw_constraint_integer — apply an integer constraint to an interval 💅

like, that's it. that's her whole job. and she ate.

🌸 SYNOPSIS 🌸

int snd_pcm_hw_constraint_integer (struct snd_pcm_runtime *runtime ,
snd_pcm_hw_param_t var );

look at that signature. chef's kiss. the space before the comma? iconic, we don't question it, we just copy it exactly 🔥

🦋 ARGUMENTS 🦋

  • runtime — the PCM runtime instance in question. your actual sound-card-in-progress situation, the whole vibe container 🫶
  • var — the hw_params variable that's getting the integer constraint slapped on it. this is the one that has to behave like a whole number, no fractions, no decimals, no "well technically 3.7" energy 💀

💖 DESCRIPTION 💖

so basically: you take an interval parameter, and you apply the constraint of integer to it. meaning that parameter is only allowed to land on integer values. that's the whole plot. no plot twist. she's a one-line legend and honestly? respect 📐✨

⭐ RETURN ⭐

  • positive 👉 if the value is changed
  • zero 👉 if it's not changed
  • a negative error code 👉 when things go sideways 😭

so yeah, check your return value. zero is not failure here, it's just "didn't need to touch it." iykyk.

🌈 SEE ALSO 🌈

bestie, buckle up, this list is long and every single one of these is getting their flowers 💐

Kernel file ./sound/core/pcm_lib.c, plus:

go read a couple of these, fr fr. the constraint family is a whole friend group and they all show up for each other 💜

🧚 sign-off 🧚

this page came out of ./sound/core (yes, the sound subsystem, the AUX cord of the kernel 🎧) and it's dated October 2026. gatekeep? no. share with your bestie. periodt. 💅🌸👑

📦 where this page comes from