trying to unpack MessagePack from C failing with "extra bytes (length should be 145)" message

[alexander-potemkin]

Hi,

I'm trying to unpack MessagePack created from latest MessagePack C library, but it fails with the following error message:

Data::MessagePack->unpack: extra bytes (length should be 145) at test.pl line 19

Here is the test.pl script (working with Pure Perl implementation):

use strict;
use Data::MessagePack;

my $dump_file_name = shift;

die "Can't file file: $dump_file_name" if (!-e $dump_file_name);

open DUMP_FILE, "<$dump_file_name"
or die "Can't open dump $dump_file_name: $!";

my $dump_content = do {local $/; <DUMP_FILE>};
close DUMP_FILE;

if (!Data::MessagePack->unpack($dump_content)) {
die "Can't unpack dump.";
}

At the same time, Python's bindings work just fine.

Any clue?

Thanks in advance.

[tokuhirom]

Can you send me a data file to reproduce?

[alexander-potemkin]

Sure, please, find it here: https://github.com/battleship-potemkin/test/blob/master/dump.cant_parse

Here is the command to reproduce:

perl test.pl dump.cant_parse

Please, let me know if any additional information required.

[syohex]

Is dump.cant_parse valid ?

% od -t x1 dump.cant_parse
0000000 87 a7 6f 73 5f 6e 61 6d 65 a5 4c 69 6e 75 78 aa
0000020 6f 73 5f 72 65 6c 65 61 73 65 ae 32 2e 36 2e 33
0000040 32 2d 33 34 31 2d 65 63 32 a9 68 6f 73 74 5f 6e
0000060 61 6d 65 ba 70 68 69 6c 6f 73 6f 70 68 65 72 2e
....

First data type is 0x87, this is fix map and it has 7 key & value pairs.
So Data::MessagePack unpack 7 keys and 7 values then it stops unpacking
and dies, because there are still not unpacking data remaining.
I think this behavior is not wrong.

You should use 'map 32' or 'map 16' for unpacking dump.cant_parse correctly.

[alexander-potemkin]

I guess it should, first of all, because Python's bindings unpack it very well.

Regarding the elements - yes, we have (were packing) 7 keys and values there.

[syohex]

dump.cant_parse has multiple data structures.

They are following

Chunk from 0 to 145
{
  'host_address' => '10.128.101.100',
  'os_arch' => 'x86_64',
  'lib_arch' => '64',
  'os_name' => 'Linux',
  'uptime' => 20396890,
  'host_name' => 'philosopher.zoo.10bees.com',
  'os_release' => '2.6.32-341-ec2'
}

Chunk from 145 to 236
{
  'buffers' => 180372,
  'swap_total' => 0,
  'total' => 650456,
  'swap_used' => 0,
  'free' => 75108,
  'swap_free' => 0,
  'used' => 575348,
  'cached' => 254320
}

Chunk from 236 to 288
{
  'system' => 0,
  'idle' => 100,
  'nice' => 0,
  'irq' => 0,
  'sintr' => 0,
  'steal' => 0,
  'wait' => 0,
  'user' => 0
}

Chunk from 288 to 1917
{
  'cpudevours' => [
                    {
                      'uid' => 0,
                      'pid' => 19349,
                      'ppid' => 11884,
                      'cpu_usage' => 1,
                      'cmdline' => './proc_sysinfo-linux-x86_64',
                      'mem_usage' => 932,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 1,
                      'ppid' => 0,
                      'cpu_usage' => 0,
                      'cmdline' => '/sbin/init',
                      'mem_usage' => 1520,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 2,
                      'ppid' => 0,
                      'cpu_usage' => 0,
                      'cmdline' => 'kthreadd',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 3,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'migration/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 4,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'ksoftirqd/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 5,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'watchdog/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 6,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'events/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 7,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'cpuset',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 8,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'khelper',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 9,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'netns',
                      'mem_usage' => 0,
                      'username' => 'root'
                    }
                  ],
  'stopped' => 0,
  'zombies' => 0,
  'sleeping' => 66,
  'memdevours' => [
                    {
                      'uid' => 101,
                      'pid' => 408,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => 'rsyslogd',
                      'mem_usage' => 1260,
                      'username' => 'syslog'
                    },
                    {
                      'uid' => 1001,
                      'pid' => 11758,
                      'ppid' => 11689,
                      'cpu_usage' => 0,
                      'cmdline' => 'sshd: alexander@pts/0',
                      'mem_usage' => 1876,
                      'username' => 'alexander'
                    },
                    {
                      'uid' => 0,
                      'pid' => 11689,
                      'ppid' => 401,
                      'cpu_usage' => 0,
                      'cmdline' => 'sshd: alexander [priv]',
                      'mem_usage' => 3432,
                      'username' => 'root'
                    },
                    {
                      'uid' => 1006,
                      'pid' => 24114,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '10bees-agent',
                      'mem_usage' => 10544,
                      'username' => '10bees'
                    },
                    {
                      'uid' => 0,
                      'pid' => 532,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '/usr/sbin/console-kit-daemon',
                      'mem_usage' => 3924,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 401,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '/usr/sbin/sshd',
                      'mem_usage' => 1660,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 11877,
                      'ppid' => 11759,
                      'cpu_usage' => 0,
                      'cmdline' => 'su',
                      'mem_usage' => 1784,
                      'username' => 'root'
                    },
                    {
                      'uid' => 107,
                      'pid' => 27770,
                      'ppid' => 27767,
                      'cpu_usage' => 0,
                      'cmdline' => 'qmgr',
                      'mem_usage' => 2384,
                      'username' => 'postfix'
                    },
                    {
                      'uid' => 107,
                      'pid' => 18667,
                      'ppid' => 27767,
                      'cpu_usage' => 0,
                      'cmdline' => 'pickup',
                      'mem_usage' => 2200,
                      'username' => 'postfix'
                    },
                    {
                      'uid' => 0,
                      'pid' => 27767,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '/usr/lib/postfix/master',
                      'mem_usage' => 2292,
                      'username' => 'root'
                    }
                  ],
  'running' => 1,
  'total' => 67
}

Chunk from 1917 to 2004
{
  'mounts' => [
                {
                  'bsize' => 4096,
                  'bfree' => 5284724,
                  'filesystem' => '/dev/sda1',
                  'mounted_on' => '/',
                  'bused' => 2972228,
                  'btotal' => 8256952
                }
              ]
}

Chunk from 2004 to 4414
{
  'nics' => [
              {
                'recv' => 3059957,
                'name' => 'eth0',
                'sent' => 4838496,
                'ipv6_addr_count' => 1,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '10.128.101.100'
                                ],
                'ipv6_addrs' => [
                                  'fe80::1031:40ff:fe00:669a'
                                ]
              },
              {
                'recv' => 0,
                'name' => 'dummy0',
                'sent' => 0,
                'ipv6_addr_count' => 0,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '0.0.0.0'
                                ],
                'ipv6_addrs' => []
              },
              {
                'recv' => 0,
                'name' => 'ifb0',
                'sent' => 0,
                'ipv6_addr_count' => 0,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '0.0.0.0'
                                ],
                'ipv6_addrs' => []
              },
              {
                'recv' => 0,
                'name' => 'ifb1',
                'sent' => 0,
                'ipv6_addr_count' => 0,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '0.0.0.0'
                                ],
                'ipv6_addrs' => []
              }
            ]
}

Data::MessagePack::unpack can unpack 1 data structure,
So Data::MessagePack::unpack unpacks only first data(7 element map)
and finish unpacking and dies(because there are still not unpacking data remaining).

You should use Data::MessagePack::Stream such case.

Sample code is following

use strict;
use warnings;
use Data::MessagePack::Stream;
use Data::Dumper;

my $dump_file_name = shift or die "Usage: $0 message_packed_file";

my $dump_content = do {
    local $/;
    open my $fh, "<", $dump_file_name or die "Can't open $dump_file_name: $!";
    <$fh>;
};

my $unpacker = Data::MessagePack::Stream->new;
$unpacker->feed($dump_content);
local $Data::Dumper::Terse = 1;
while ($unpacker->next) {
    print Dumper($unpacker->data);
}

And I get following output same as above

% perl stream.pl dump.cant_parse
{
  'host_address' => '10.128.101.100',
  'os_arch' => 'x86_64',
  'lib_arch' => '64',
  'os_name' => 'Linux',
  'uptime' => 20396890,
  'host_name' => 'philosopher.zoo.10bees.com',
  'os_release' => '2.6.32-341-ec2'
}
{
  'buffers' => 180372,
  'swap_total' => 0,
  'total' => 650456,
  'swap_used' => 0,
  'free' => 75108,
  'swap_free' => 0,
  'used' => 575348,
  'cached' => 254320
}
{
  'system' => 0,
  'idle' => 100,
  'nice' => 0,
  'irq' => 0,
  'sintr' => 0,
  'steal' => 0,
  'wait' => 0,
  'user' => 0
}
{
  'cpudevours' => [
                    {
                      'uid' => 0,
                      'pid' => 19349,
                      'ppid' => 11884,
                      'cpu_usage' => 1,
                      'cmdline' => './proc_sysinfo-linux-x86_64',
                      'mem_usage' => 932,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 1,
                      'ppid' => 0,
                      'cpu_usage' => 0,
                      'cmdline' => '/sbin/init',
                      'mem_usage' => 1520,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 2,
                      'ppid' => 0,
                      'cpu_usage' => 0,
                      'cmdline' => 'kthreadd',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 3,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'migration/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 4,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'ksoftirqd/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 5,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'watchdog/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 6,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'events/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 7,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'cpuset',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 8,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'khelper',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 9,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'netns',
                      'mem_usage' => 0,
                      'username' => 'root'
                    }
                  ],
  'stopped' => 0,
  'zombies' => 0,
  'sleeping' => 66,
  'memdevours' => [
                    {
                      'uid' => 101,
                      'pid' => 408,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => 'rsyslogd',
                      'mem_usage' => 1260,
                      'username' => 'syslog'
                    },
                    {
                      'uid' => 1001,
                      'pid' => 11758,
                      'ppid' => 11689,
                      'cpu_usage' => 0,
                      'cmdline' => 'sshd: alexander@pts/0',
                      'mem_usage' => 1876,
                      'username' => 'alexander'
                    },
                    {
                      'uid' => 0,
                      'pid' => 11689,
                      'ppid' => 401,
                      'cpu_usage' => 0,
                      'cmdline' => 'sshd: alexander [priv]',
                      'mem_usage' => 3432,
                      'username' => 'root'
                    },
                    {
                      'uid' => 1006,
                      'pid' => 24114,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '10bees-agent',
                      'mem_usage' => 10544,
                      'username' => '10bees'
                    },
                    {
                      'uid' => 0,
                      'pid' => 532,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '/usr/sbin/console-kit-daemon',
                      'mem_usage' => 3924,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 401,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '/usr/sbin/sshd',
                      'mem_usage' => 1660,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 11877,
                      'ppid' => 11759,
                      'cpu_usage' => 0,
                      'cmdline' => 'su',
                      'mem_usage' => 1784,
                      'username' => 'root'
                    },
                    {
                      'uid' => 107,
                      'pid' => 27770,
                      'ppid' => 27767,
                      'cpu_usage' => 0,
                      'cmdline' => 'qmgr',
                      'mem_usage' => 2384,
                      'username' => 'postfix'
                    },
                    {
                      'uid' => 107,
                      'pid' => 18667,
                      'ppid' => 27767,
                      'cpu_usage' => 0,
                      'cmdline' => 'pickup',
                      'mem_usage' => 2200,
                      'username' => 'postfix'
                    },
                    {
                      'uid' => 0,
                      'pid' => 27767,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '/usr/lib/postfix/master',
                      'mem_usage' => 2292,
                      'username' => 'root'
                    }
                  ],
  'running' => 1,
  'total' => 67
}
{
  'mounts' => [
                {
                  'bsize' => 4096,
                  'bfree' => 5284724,
                  'filesystem' => '/dev/sda1',
                  'mounted_on' => '/',
                  'bused' => 2972228,
                  'btotal' => 8256952
                }
              ]
}
{
  'nics' => [
              {
                'recv' => 3059957,
                'name' => 'eth0',
                'sent' => 4838496,
                'ipv6_addr_count' => 1,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '10.128.101.100'
                                ],
                'ipv6_addrs' => [
                                  'fe80::1031:40ff:fe00:669a'
                                ]
              },
              {
                'recv' => 0,
                'name' => 'dummy0',
                'sent' => 0,
                'ipv6_addr_count' => 0,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '0.0.0.0'
                                ],
                'ipv6_addrs' => []
              },
              {
                'recv' => 0,
                'name' => 'ifb0',
                'sent' => 0,
                'ipv6_addr_count' => 0,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '0.0.0.0'
                                ],
                'ipv6_addrs' => []
              },
              {
                'recv' => 0,
                'name' => 'ifb1',
                'sent' => 0,
                'ipv6_addr_count' => 0,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '0.0.0.0'
                                ],
                'ipv6_addrs' => []
              }
            ]
}

[alexander-potemkin]

Thanks. Any way for the streams to be unpacked by using Pure Perl solution? Or, at least, to verify the structure without using C library?

[syohex]

You can use Data::MessagePack::PP::Unpacker(Pure perl implementation of Data::MessagePack::Unpacker).
But author says "Data::MessagePack::Unpacker is deprecated, use Data::MessagePack::Stream instead".

Sample code is following.

use strict;
use warnings;
use Data::MessagePack;
use Data::Dumper;

my $dump_file_name = shift or die "Usage: $0 message_packed_file";

my $dump_content = do {
    local $/;
    open my $fh, "<", $dump_file_name or die "Can't open $dump_file_name: $!";
    <$fh>;
};

local $Data::Dumper::Terse = 1;
my $unpacker = Data::MessagePack::Unpacker->new;

my $limit = length $dump_content;
my $off = 0;
while (1) {
    $off = $unpacker->execute($dump_content, $off);
    print Dumper($unpacker->data);

    $unpacker->reset;
    last if $off >= $limit;
}

output is

% PERL_ONLY=1 perl pp_stream.pl dump.cant_parse
{
  'host_address' => '10.128.101.100',
  'os_arch' => 'x86_64',
  'lib_arch' => '64',
  'os_name' => 'Linux',
  'uptime' => 20396890,
  'host_name' => 'philosopher.zoo.10bees.com',
  'os_release' => '2.6.32-341-ec2'
}
{
  'buffers' => 180372,
  'swap_total' => 0,
  'total' => 650456,
  'swap_used' => 0,
  'free' => 75108,
  'swap_free' => 0,
  'used' => 575348,
  'cached' => 254320
}
{
  'system' => 0,
  'idle' => 100,
  'nice' => 0,
  'irq' => 0,
  'sintr' => 0,
  'steal' => 0,
  'wait' => 0,
  'user' => 0
}
{
  'cpudevours' => [
                    {
                      'uid' => 0,
                      'pid' => 19349,
                      'ppid' => 11884,
                      'cpu_usage' => 1,
                      'cmdline' => './proc_sysinfo-linux-x86_64',
                      'mem_usage' => 932,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 1,
                      'ppid' => 0,
                      'cpu_usage' => 0,
                      'cmdline' => '/sbin/init',
                      'mem_usage' => 1520,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 2,
                      'ppid' => 0,
                      'cpu_usage' => 0,
                      'cmdline' => 'kthreadd',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 3,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'migration/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 4,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'ksoftirqd/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 5,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'watchdog/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 6,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'events/0',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 7,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'cpuset',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 8,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'khelper',
                      'mem_usage' => 0,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 9,
                      'ppid' => 2,
                      'cpu_usage' => 0,
                      'cmdline' => 'netns',
                      'mem_usage' => 0,
                      'username' => 'root'
                    }
                  ],
  'stopped' => 0,
  'zombies' => 0,
  'sleeping' => 66,
  'memdevours' => [
                    {
                      'uid' => 101,
                      'pid' => 408,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => 'rsyslogd',
                      'mem_usage' => 1260,
                      'username' => 'syslog'
                    },
                    {
                      'uid' => 1001,
                      'pid' => 11758,
                      'ppid' => 11689,
                      'cpu_usage' => 0,
                      'cmdline' => 'sshd: alexander@pts/0',
                      'mem_usage' => 1876,
                      'username' => 'alexander'
                    },
                    {
                      'uid' => 0,
                      'pid' => 11689,
                      'ppid' => 401,
                      'cpu_usage' => 0,
                      'cmdline' => 'sshd: alexander [priv]',
                      'mem_usage' => 3432,
                      'username' => 'root'
                    },
                    {
                      'uid' => 1006,
                      'pid' => 24114,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '10bees-agent',
                      'mem_usage' => 10544,
                      'username' => '10bees'
                    },
                    {
                      'uid' => 0,
                      'pid' => 532,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '/usr/sbin/console-kit-daemon',
                      'mem_usage' => 3924,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 401,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '/usr/sbin/sshd',
                      'mem_usage' => 1660,
                      'username' => 'root'
                    },
                    {
                      'uid' => 0,
                      'pid' => 11877,
                      'ppid' => 11759,
                      'cpu_usage' => 0,
                      'cmdline' => 'su',
                      'mem_usage' => 1784,
                      'username' => 'root'
                    },
                    {
                      'uid' => 107,
                      'pid' => 27770,
                      'ppid' => 27767,
                      'cpu_usage' => 0,
                      'cmdline' => 'qmgr',
                      'mem_usage' => 2384,
                      'username' => 'postfix'
                    },
                    {
                      'uid' => 107,
                      'pid' => 18667,
                      'ppid' => 27767,
                      'cpu_usage' => 0,
                      'cmdline' => 'pickup',
                      'mem_usage' => 2200,
                      'username' => 'postfix'
                    },
                    {
                      'uid' => 0,
                      'pid' => 27767,
                      'ppid' => 1,
                      'cpu_usage' => 0,
                      'cmdline' => '/usr/lib/postfix/master',
                      'mem_usage' => 2292,
                      'username' => 'root'
                    }
                  ],
  'running' => 1,
  'total' => 67
}
{
  'mounts' => [
                {
                  'bsize' => 4096,
                  'bfree' => 5284724,
                  'filesystem' => '/dev/sda1',
                  'mounted_on' => '/',
                  'bused' => 2972228,
                  'btotal' => 8256952
                }
              ]
}
{
  'nics' => [
              {
                'recv' => 3059957,
                'name' => 'eth0',
                'sent' => 4838496,
                'ipv6_addr_count' => 1,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '10.128.101.100'
                                ],
                'ipv6_addrs' => [
                                  'fe80::1031:40ff:fe00:669a'
                                ]
              },
              {
                'recv' => 0,
                'name' => 'dummy0',
                'sent' => 0,
                'ipv6_addr_count' => 0,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '0.0.0.0'
                                ],
                'ipv6_addrs' => []
              },
              {
                'recv' => 0,
                'name' => 'ifb0',
                'sent' => 0,
                'ipv6_addr_count' => 0,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '0.0.0.0'
                                ],
                'ipv6_addrs' => []
              },
              {
                'recv' => 0,
                'name' => 'ifb1',
                'sent' => 0,
                'ipv6_addr_count' => 0,
                'ipv4_addr_count' => 1,
                'ipv4_addrs' => [
                                  '0.0.0.0'
                                ],
                'ipv6_addrs' => []
              }
            ]
}

[alexander-potemkin]

Lovely, it works now.

Hope the module will keep working as it's the only Pure Perl unpack implementation available.

Thanks syohex, tokuhirom for prompt reply, great help and scripts examples!