monitor mic input

[Karl Auer]

What is the simplest - preferably command line - way to get microphone
input happening on headphone output?

I know I can fire up Audacity, but that is a hammer for a gnat... and
needs X.

Regards, K.

-- 
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Karl Auer (kauer at biplane.com.au)
http://www.biplane.com.au/kauer
http://twitter.com/kauer389

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