As someone has already mentioned IO::Uncompress::Unzip has a filehandle interface that hides all the complexity of reading directly from a zip file. Looking at the post from few days ago, the commented block below showed reading from the zip file 
#  my $sn=$fips2state->{$sfips}.'2010.sf1'; 
#  my $zf=$dir0.'/sf1/'.$sn.'.zip';
#  my $mf=$fips2state->{$fips}.'geo2010.sf1'; ; 
#  my $member=zipbyline_start($zf,$mf); 
#  while (my $line=zipbyline_read($member)){ 
#    ... pull out datums AREALAND AREAWATR POP100, create density 
#    } # line   
#  zipbyline_close($member);

[download]

That would become this with IO::Uncompress::Unzip 

use IO::Uncompress::Unzip;

my $sn=$fips2state->{$sfips}.'2010.sf1'; 
my $zf=$dir0.'/sf1/'.$sn.'.zip';
my $mf=$fips2state->{$fips}.'geo2010.sf1'; ;

my $member = IO::Uncompress::Unzip($zf, Name => $mf);
while (<$member>)
{
    #... pull out datums AREALAND AREAWATR POP100, create density 

}
close $member;

[download]

In reply to Re^5: Geo::ShapeFile memory problem by pmqs
in thread Geo::ShapeFile memory problem by rhzhang

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