using /bin/sh vars in awk

[andre]

In article <27814 at neptune.inf.ethz.ch> gaspar at inf.ethz.ch (Scott "gaspo" Gasparian) writes:

  >Question: what syntax do I have to use to get awk to take /bin/sh
  >          variables in a shell script?

  >Example:  given a /bin/sh script, and an awk command in it somewheres,
  >          and i need to pass the var ${fred} to awk, what should
  >          the following line look like?

  >          fred="barney"
  >          wilma=`cat ${file1} | awk '{if($1== fred ){print("match")}}'
  >                                              ^^^^
  >             what I need is how to expand fred_|  to get awk to
  >          replace it with the string "barney"
  >
  >Since this already came up, just email me the answer.  I've already
  >tried ${fred}, $fred, "${fred}" and a couple other combos.

Your problem is that you put the wak problam inside single ' quotes
and the shell will not expand variables in there no matter how you
try. (that's the good thing about single quotes).

If you want to expand a variable inside such a string, you must
end the quoted part, expand the variable and start the quotation
again. To be sure that it stays 1 argument if there are spaces
in the variable use double quotes to keep them together.

In your case this becomes:

  wilma=`cat ${file1} | awk '{if($1== '"$fred"' ){print("match")}}'

	hope this helps
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