Shell Programming and Scripting

cat postalfile.txt | grep -f zipcodes.txt

$ cat postalfile.txt |head -3
MS         JOAMARA        ARTE              44 SECTOR LA PLAYITA                            ADJUNTAS     PR005412312
MS         JULIA          ALIFEA            44 CALLE JOHN F KENNEDY                         ADJUNTAS     PR006012
MS         MARCENE        SERVANA           44 CALLE SAN JOAQUIN                            ADJUNTAS     PR006012137

grep -f zipcodes.txt postalfile.txt

MS         MARLENE       SERBRANO           14044 W 174TH ST          APT 7B                        BRONX        NY10453
MS         YANIRA        GAPONTE            34126 CRESCENT DR                                       CHICOPEE     MA01013
MS         BETZAIDA      JACOBSEN           41102 HAMILTON AVE         APT 3                         LYNN         MA01902

while read LINE
do
    ZIP=${LINE:148:5} # first pos. has index 0
    if grep -f $ZIP zipcodes.txt
    then
        ....
    fi
done < postalfile.txt

awk 'NF==1 { ++A[$0] } NF>1 {s=substr($0,149,8)} A[s]'  zip_file dat_file