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Example:

$ apropos alsa
aconnect (1) - ALSA sequencer connection manager
alsaconf (8) - configuration tool for the Advanced Linux Sound Architecture
alsactl (1) - advanced controls for ALSA soundcard driver
alsamixer (1) - soundcard mixer for ALSA soundcard driver, with ncurses interface
amidi (1) - read from and write to ALSA RawMIDI ports
amixer (1) - command-line mixer for ALSA soundcard driver
aplay (1) - command-line sound recorder and player for ALSA soundcard driver
arecord (1) - command-line sound recorder and player for ALSA soundcard driver
aseqnet (1) - ALSA sequencer connectors over network
speaker-test (1) - command-line speaker test tone generator for ALSA

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