A more concise `df` command

df.sh

#!/bin/sh

/bin/df -h "$@" 2>/dev/null | perl -e '
    $prefix     = <>;
    $longest_fs = 20;
    
    while ( <> ) {
    m{
        ^ 
        ( [\S+\s]+? ) \s+   # Filesystem
        (\S+) \s+           # Size
        (\S+) \s+           # Used
        (\S+) \s+           # Avail
        (\S+) \s+           # Capacity (%)
        (?:
            \S+ \s+         # iused
            \S+ \s+         # ifree
            \S+ \s+         # %iused
        )
        (/.*)               # Mounted on
        $
    }x;
    
    push @fs, [ $6, $2, $3, $4, $5 ];
        $longest_fs = length( $6 ) if length $6 > $longest_fs;
    }
    
    $tmpl = "%-${longest_fs}s %9s %9s %9s %9s\n";
    
    printf $tmpl, "Mounted on", qw( Size Used Avail Capacity );
    foreach my $fs ( @fs ) {
        printf $tmpl, @{ $fs };
    }
'