Shell Programming and Scripting

123
324
456
235
456

abc one 000 123 abc
abc one 000 456 abc
abc one 000 122 abc
abc one 000 111 abc

abc one 000 122 abc
abc one 000 111 abc

awk 'FILENAME=="one.txt" {arr[$1]++}
        FILENAME=="two.txt" {
              if($4 in arr){next}
              print $0
         }  ' one.txt  two.txt > new2.txt

awk 'FNR==NR{X[$4]=$0;next} ($1 in X){;delete X[$1]} END{for(i in X){print X[i]}}' two.txt one.txt

abc one 000 111 abc
abc one 000 122 abc