UNIX for Dummies Questions & Answers

$ echo "one two three" | awk '{$3="my tree"; print $0}'
one two my tree

$ var="my tree"
$ echo "one two three" | awk '{$3="'$var'"; print $0}'
awk: {$3="my
awk:     ^ unterminated string

 
$ var="test"
$ echo "one two three" | awk '{$3="'$var'"; print $0}'
one two test
 
$ echo "one two three" | nawk -v var=$var '{$3=var;print $0}'
one two test

 
$ echo $var
my test

$ echo "one two three" | nawk -v var="$var" '{$3=var;print $0}'  
one two my test

awk '{$3="'$var'"; print $0}'

awk '{$3="'my tree'"; print $0}'

 '{$3="'my

tree'"; print $0}'