snd_pcm_stream_str(9)

💅 snd_pcm_stream_str(9) — the Kernel API Manual, but make it make sense 🎀

okay so bestie, welcome to snd_pcm_stream_str(9) from the Kernel API Manual ✨ this one is genuinely so chill — it's the little helper that tells you which way your audio stream is pointing. no cap, it's a one-job icon.

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🌸 NAME 🌸

snd_pcm_stream_str — get a string naming the direction of a stream 🧭

like, you hand it a substream and it gives you back words that describe which way the sound is going. that's it. that's the whole vibe.

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✨ SYNOPSIS ✨

const char * snd_pcm_stream_str (struct snd_pcm_substream *substream );

that's the whole call, bestie — one argument, one const char * back. no drama, no side quests 💅

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🦋 ARGUMENTS 🦋

• substream — the pcm substream instance. that's the thing you're asking about, the little stream baby in question 🍼

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👑 RETURN 👑

a string naming the direction of the stream. that's literally it — a string, naming the direction, of the stream. iconic behavior, no notes 💖

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🌈 SEE ALSO 🌈

okay this is the part where the manpage just dumps the entire friend group on you, and honestly? respect. here's everyone in the group chat, and you should keep them exactly as written because these are real symbols, fr fr 🫶

• Kernel file ./include/sound/pcm.h — the file you want, iykyk 📁
• snd_pcm_stream_linked(9)
• snd_pcm_stream_lock_irqsave(9)
• snd_pcm_stream_lock_irqsave_nested(9)
• snd_pcm_group_for_each_entry(9)
• snd_pcm_running(9)
• __snd_pcm_set_state(9)
• bytes_to_samples(9)
• bytes_to_frames(9)
• samples_to_bytes(9)
• frames_to_bytes(9)
• frame_aligned(9)
• snd_pcm_lib_buffer_bytes(9)
• snd_pcm_lib_period_bytes(9)
• snd_pcm_playback_avail(9)
• snd_pcm_capture_avail(9)
• snd_pcm_playback_hw_avail(9)
• snd_pcm_capture_hw_avail(9)
• snd_pcm_playback_ready(9)
• snd_pcm_capture_ready(9)
• snd_pcm_playback_data(9)
• snd_pcm_playback_empty(9)
• snd_pcm_capture_empty(9)
• snd_pcm_trigger_done(9)
• params_channels(9)
• params_rate(9)
• params_period_size(9)
• params_periods(9)
• params_buffer_size(9)
• params_buffer_bytes(9)
• snd_pcm_hw_constraint_single(9)
• snd_pcm_format_cpu_endian(9)
• snd_pcm_set_sync(9)
• snd_pcm_set_runtime_buffer(9)
• snd_pcm_gettime(9)
• snd_pcm_set_fixed_buffer(9)
• snd_pcm_set_fixed_buffer_all(9)
• snd_pcm_sgbuf_get_addr(9)
• snd_pcm_sgbuf_get_chunk_size(9)
• snd_pcm_limit_isa_dma_size(9)
• snd_pcm_direction_name(9)
• snd_pcm_chmap_substream(9)
• pcm_format_to_bits(9)
• pcm_for_each_format(9)

real talk: that's the whole list, don't skip any of them, they're all (9) sections and they're all invited to the party 🎉

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and that's the page, bestie!! this beauty lives under ./include/sound, and the doc fairies stamped it October 2026 — so go forth, name some stream directions, and slay 💅✨🎀