Generates a Morse-code tones (actual sound, not a dots and dashes on the screen).
Usage examples (only the first three work correctly on my system):
echo CW forever | ./cw.sed > /dev/dsp
echo Hi | ./cw.sed | aplay -Dplug:default
echo Message | ./cw.sed | sox -t raw -r 8k -c 1 -e unsigned -b 8 - -d
echo Hi | ./cw.sed | aplay -r 64000
echo Hi | ./cw.sed | aplay -r 8000 -c 2
echo Message | ./cw.sed | sox -t raw -r 64k -c 1 -e unsigned -b 8 - -dN.B., Written for the GNU sed.