Extract references

#!/bin/awk -f
BEGIN {
        FS ="$"
}
{
        n = NF;
        while ( n > 0 ) {
                if ( $n == "" ) {
                        break;
                }
                if ( match($n, /(([[:alpha:]]\w*)|([[:digit:]]+))/) > 0 && ( $(n-1) !~ /\'$/i || n-1 == 0 ) ) {
                        #find char position of reference relative to line (record).
                        i = 1;
                        c = 1; #counter for $ in line ($0)
                        while ( c != n) {
                                if  ( substr($0, i, 1) == "$" ) {
                                        c++;
                                }
                                i++;
                        }
                        #output the match string line position and line number
                        if ( ( i - 2 > 0 && substr($0, i - 2, 2) ~ /^[^\$]\$$/ ) ) {
                                print substr($n, RSTART, RLENGTH), i, NR;
                        } else if ( (i - 2 == 0 && substr($0, i-1, 1) == "$" ) ){
                                print substr($n, RSTART, RLENGTH), i, NR;
                        }
                }
                n--;
        }
}