1   2   3   4   5   6   7   8   9   0
       0   0   0   0   0   0   0   0   0   0  Filesystem (avail)
    ---|---|---|---|---|---|---|---|---|---|  ------------------
 89 ===================================       /dos (704936)
 62 ========================                  /usr (4555040)
 62 ========================                  /home/lemur (4555040)
 45 ==================                        / (134353)

##</code><code>##

#!/usr/bin/perl

use Term::ANSIColor qw( color );

my @lines;
my $df = "df";

## Point to a Berkely-esque df if needed
if ($^O =~ /solaris/) {
  $df = "/usr/ucb/df";
}

## Open a pipe from df
open( DF, "$df @ARGV |" ) or die "Can't open pipe from df: $!"; 

## skip first line
scalar <DF>; 

## Print header
print "                                           1\n",
      "       1   2   3   4   5   6   7   8   9   0\n",
      "       0   0   0   0   0   0   0   0   0   0  Filesystem (avail)\n",
      "    ---|---|---|---|---|---|---|---|---|---|  ------------------\n"; 

## Parse output from df
while(<DF>) { 
  chomp; 
  my @F = split;
  $_ .= <DF>, @F = split if @F == 1;

  my( $av, $c, $fs ) = @F[3, 4,-1]; 
  $c =~ s/(\d+)%/$1/;

  push @lines, [ $c, sprintf "%3d %-40s  %s (%d)", $c, 
                                                "=" x int($c / 2.5),
                                                $fs, $av ]; 
} 

close(DF);

## Print sorted reverse by capacity
for( sort { $b->[0] <=> $a->[0] } @lines ) {
  my $color = '';
  if ( $_->[0] >= 85 ) {
    $color = color( 'bold red' );
  } elsif ( $_->[0] >= 70 ) {
    $color = color( 'bold yellow' );
  }

  print $color, $_->[1], color('reset'), "\n";
}

exit 0;

__END__