#!/usr/bin/perl -w

use strict;

my @df = `df -k`;		# get filesystem listing
shift @df;			# lose the header

my %df;
for (@df) { 
  # go through each line, splitting it out into columns and storing
  # that in a hash-of-hashes:
  my ($disk, $blks, $used, $avail, $cap, $mount)= split;
  $df{$disk} = { blocks => $blks,
		 used => $used,
		 available => $avail,
		 capacity => $cap,
		 mount => $mount };
}

# find the root file system, and how much room is left on it:
my ($root) = grep { $df{$_}{mount} eq "/" } keys %df;
print "root disk = $root; available = $df{$root}{available} kB\n";

# get total available space on system:
my $total_avail = 0;
foreach my $avail (map { $_->{available} } values %df) {
  $total_avail += $avail;
}
print "total available = ${total_avail} kB\n";

exit 0;