Shell Programming and Scripting

#!/usr/bin/perl


open (FW, "> outputfile.csv");
$filename = shift;

while (@ARGV) {
$text1 = shift;
$text2 = shift;

$ret=`grep $text2 $filename`;

chomp $ret;
$ret =~ s/$text2/$text1/g;

print FW $ret,"\n";

}

close (FW);

MHF ABC
JHT DPG

awk -F, 'NR==FNR{a[$2]=$1;next}
a[$1]{$1=a[$1]}1
' OFS="," ref.file input.file > newfile.csv

package Temp;
sub TIEHASH{
	my $class = shift;
	my $file= $_[0];
	my %hash;
	open FH,"<$file";
	while(<FH>){
		chomp;
		my @tmp = split(",",$_,2);
		$hash{$tmp[0]}=$tmp[1];
	}
	close FH;
	my $self ={};
	$self->{DATA}=\%hash;
	$self->{KEY}=$_[1];
	return bless $self,$class;
}
sub FETCH{
	return $_[0]->{DATA}->{$_[0]->{KEY}->{$_[1]}};
}
1

use Temp;
my %hash1=(KEY1=>'PDR',KEY2=>'ABC',KEY3=>'MPG');
tie %hash,"Temp","yourfile.txt",\%hash1;
print $hash{'KEY1'},",KEY1\n";