use File::Tail;

sub reading_updated_file
{
	my $path=shift;
	my $count=0;
	my $file=File::Tail->new($path);
	while(defined (my $read=$file->read))
	{
      if($read =~ /string_to_match/)
		{ 
		  $count++;
	       last if $count ==3;
	      
		}

	print "here doing rest statements";
	}

	
}
&reading_updated_file("path of file_to tail");