snd_pcm_running(9)

💅 snd_pcm_running(9) — the "is this thing actually playing rn" check

okay so bestie, welcome to the Kernel API Manual ✨ this one lives in snd_pcm_running(9) and it's literally the vibe check for your PCM substream 🔥

🌸 NAME

snd_pcm_running — checks whether the substream is in a running state 🏃‍♀️💨

✨ SYNOPSIS

int snd_pcm_running (struct snd_pcm_substream *substream );

🎀 ARGUMENTS

• substream — the substream you wanna check, bestie 👀 that's the whole thing

🫶 RETURN

It returns true if the substream you handed it is in the state RUNNING, or if it's in the state DRAINING for playback 💖

no cap, DRAINING only counts for playback — that's the fine print, don't forget it 🙈

🌈 SEE ALSO

Kernel file ./include/sound/pcm.h 📁 and honestly the whole friend group is here:

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_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_stream_str(9), snd_pcm_chmap_substream(9), pcm_format_to_bits(9), pcm_for_each_format(9)

okay that's the whole page, mwah 💋 it's filed under ./include/sound, dated October 2026 — that's the source and the date bestie, and snd_pcm_running(9) is the name of the game 👑 go check those substreams, ily, bye 🦋💜