UNIX for Dummies Questions & Answers

awk ' { if(index($0, "green" )>0)  {print $0; next}
          if(index($0, "red") >0 ) {next}
          print $0
        } ' inputfile > newfile

while read line
do
     echo $line | grep -i red > /dev/null
     if [ $? -eq 0 ]
     then
         echo $line | grep -i green > /dev/null
         if [ $? -eq 0 ]
         then
              echo $line >> new_file
         fi
     else
         echo $line >> new_file
     fi
done < input_file

 cat temp.txt  | perl -ne 'if(/green/i){print;}else{print unless /red/i} '

awk '/red/&&!/green/{next}1' infile

sed '/red/{/green/!d;}' infile

perl -ne'print unless/red/&&!/green/' infile