#!/usr/bin/env perl
use warnings;
use strict;
use File::Spec;
use Getopt::Std;
use Fcntl;
use constant BUF_SIZE => 4096;
use lib
'/home/myself/perl5/perls/perl-5.20.1/lib/site_perl/5.20.3/i686-linux/sys';
require 'syscall.ph';

my %opts;

getopts( 'd:', \%opts );

die 'option -d <DIRECTORY> is required'
  unless ( ( exists( $opts{d} ) ) and ( defined( $opts{d} ) ) );

sysopen( my $fd, $opts{d}, O_RDONLY | O_DIRECTORY );

while (1) {

    my $buf = "\0" x BUF_SIZE;
    my $read = syscall( &SYS_getdents, fileno($fd), $buf, BUF_SIZE );

    if ( ( $read == -1 ) and ( $! != 0 ) ) {
        die "failed to syscal getdents: $!";
    }

    last if ( $read == 0 );

    while ( $read != 0 ) {
        my ( $ino, $off, $len, $name ) = unpack( "LLSZ*", $buf );

        #print $name, "\n" if ( $ino != 0 );
        unless ( ( $name eq '.' ) or ( $name eq '..' ) ) {
            my $path = File::Spec->catfile( $opts{d}, $name );
            unlink $path or die "Cannot remove $path: $!";
        }
        substr( $buf, 0, $len ) = '';
        $read -= $len;
    }

}

close($fd);