eject - 2.40.2-12 main

This program will eject CD-ROMs (assuming your drive supports the CDROMEJECT
ioctl). It also allows setting the autoeject feature.
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On supported ATAPI/IDE multi-disc CD-ROM changers, it allows changing
the active disc.
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You can also use eject to properly disconnect external mass-storage
devices like digital cameras or portable music players.