How to pass shell variables to awk?

[Peter Scott]

Maybe this one should be in the FAQ; I know it came through here
several months ago, but I forgot the answer until, of course, I
wanted to do it myself.

Now I have a workaround, so I'm interested in the answer only
for academic reasons (until I need to do it again...); if I have
some (csh) variable foo and I want awk to recognize it, e.g.
awk file '{print $1-?$foo?}', what would I use instead of ? and ? ?
Thanks!


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This is news.  This is your       |    Peter Scott, NASA/JPL/Caltech
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