/ 
Unix-Statgrab-0.03
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/ Unix::Statgrab

NAME

Unix::Statgrab - Perl extension for collecting information about the machine

SYNOPSIS

    use Unix::Statgrab;

    local $, = "\n";
    
    my $host = get_host_info or 
	die get_error;
	
    print $host->os_name, 
	  $host->os_release,
	  $host->os_version,
	  ...;

    my $disks = get_disk_io_stats or
	die get_error;
	
    for (0 .. $disks->num_disks - 1) {
	print $disks->disk_name($_),
	      $disks->read_bytes($_),
	      ...;
    }

DESCRIPTION

Unix::Statgrab is a wrapper for libstatgrab as available from http://www.i-scream.org/libstatgrab/. It is a reasonably portable attempt to query interesting stats about your computer. It covers information on the operating system, CPU, memory usage, network interfaces, hard-disks etc.

Each of the provided functions follow a simple rule: It never takes any argument and returns either an object (in case of success) or undef. In case undef was returned, check the return value of get_error. Also see "ERROR HANDLING" further below.

FUNCTIONS

drop_privileges()

Unix::Statgrab can be told to discard setuid and setgid privileges which is usually a good thing. If your program doesn't need the elevated privileges somewhere else, call it right after useing the module.

get_host_info()

Returns generic information about this machine. The object it returns supports the following methods:

  • os_name

  • os_release

  • os_version

  • platform

  • hostname

  • uptime

get_cpu_stats

Returns information about this machine's usage of the CPU. The object it returns supports the following methods, all of which return the number of ticks the processor has spent in the respective states:

  • user

  • kernel

  • idle

  • iowait

  • swap

  • nice

  • total

  • systime

    The system time in seconds.

get_cpu_stats_diff

Returns the differences in ticks for each of the states since last time get_cpu_stats or get_cpu_stats_diff was called. If cpu_get_stats_diff is called for the first time (and get_cpu_stats wasn't called before) its return values will be the same as get_cpu_stats.

Its return value supports the same methods as get_cpu_stats. systime then will be the seconds since the last call of this function.

get_cpu_percents

Calls get_cpu_stats_diff under the hood but instead of returning ticks, it returns percentages. Its return value provides the same methods as get_cpu_stats and get_cpu_stats_diff.

get_disk_io_stats

Returns the disk IO per disk stored in the kernel which holds the amount of data transferred since bootup. Unlike most other methods presented in this manpage, the methods you can call on its return value take an additional optional parameter which specifies which disk you want information about. If you do not provide this parameter, 0 (= first disk) is assumed.

  • num_disks

    The number of disks that were found on this machine.

  • disk_name($disk)

  • read_bytes($disk)

  • write_bytes($disk)

  • systime($disk)

    The system time in seconds over which read_bytes and write_bytes were transferred.

get_disk_io_stats_diff

The same as get_disk_io_stats except that it will report the difference to the last call of either get_disk_io_stats or get_disk_io_stats_diff. Provides the same methods as get_disk_io_stats.

get_fs_stats

Returns statistics about the mounted filesystems, including free space and inode usage. The provided methods again take one optional argument which specifies which partition you want information about. If you do not provide this parameter, 0 (= first mounted filesystem) is assumed:

  • num_fs

    The number of mounted filesystems that were found on this machine.

  • device_name($fs)

  • fs_type($fs)

  • mnt_point($fs)

  • size($fs)

    Size in bytes.

  • used($fs)

  • avail($fs)

  • total_inodes($fs)

  • used_inodes($fs)

  • free_inodes($fs)

get_load_stats()

Returns the load average over various span of times. The following methods are provided:

  • min1

    Load average over 1 minute.

  • min5

  • min15

get_mem_stats()

Returns statistics about memory usage. The following methods exist:

  • total

    Total memory in bytes.

  • free

  • used

  • cache

    Amount of cache used in bytes.

get_swap_stats()

Returns statistics about swap usage. The following methods exist:

  • total

    Total swap memory in bytes.

  • used

  • free

get_network_io_stats()

Returns statistics about the network traffic per network interface as stored in the kernel. Again, the provided methods support one optional parameter specifiying which network interface to query. If the parameter is missing, 0 (= first interface) is assumed.

  • num_ifaces

    The number of network interfaces found on your machine.

  • interface_name($if)

  • tx($if)

    The number of bytes transmitted.

  • rx($if)

    The number of bytes received.

  • ipackets($if)

    The number of packets received.

  • opackets($if)

    The number of bytes transmitted.

  • ierrors($if)

    The number of receive errors

  • oerrors($if)

    The number of transmit errors

  • collisions($if)

  • systime

    The time period over which tx and rx were transferred.

get_network_io_stats_diff()

The same as get_network_io_stats except that it will report on the difference to the last time get_network_io_stats or get_network_io_stats_diff was called. It supports the same methods as get_network_io_stats.

get_network_iface_stats()

Returns statistics about each of the found network interfaces in your computer. The provided methods take one optional argument being the interface to query. If this parameter is missing, 0 (= first interface) is assumed.

  • num_ifaces

    The number of interfaces found.

  • interface_name($if)

  • speed($if)

    The speed of the interface, in megabits/sec

  • dup($if)

    One of SG_IFACE_DUPLEX_FULL, SG_IFACE_DUPLEX_HALF and SG_IFACE_DUPLEX_UNKNOWN. Unknown could mean that duplex hasn't been negotiated yet.

  • up($if)

    Whether the interface is up.

get_page_stats()

Returns the number of pages the system has paged in and out since bootup. It supports the following methods:

  • pages_pagein

  • pages_pageout

  • systime

    The time period over which pages_pagein and pages_pageout were transferred, in seconds.

get_page_stats_diff()

The same as get_page_stats except that it will report the difference to the last time get_page_stats or get_page_stats_diff was called. Supports the same methods as get_page_stats.

get_user_stats()

Returns information about the currently logged in users. It supports the following methods:

  • num_entries

    The number of currently logged in users.

  • name_list

    A list of the users currently logged in.

get_process_stats()

Returns loads of information about the current processes. This function only returns a container. If you want to look at the processes returned, call all_procs on its return value.

The processes can also be sorted by various criteria by using the sort_by method. This will change the internal order of the container. This method returns the container object so you can do some method chaining:

    my $procs = get_process_stats;
    $procs->sort_by("name");
    print $_->proc_name, "\n" foreach $procs->all_procs;

    # syntactically sweeter

    print $_->proc_name, "\n" 
	foreach get_process_stats->sort_by("name")->all_procs;

Available sorting methods are "name", "pid", "uid", "gid", "size", "res", "cpu" and "time".

You can also sort the list returned by all_procs. For that you can use one of the eight sorting routines thusly:

my $p = get_process_stats;

my @by_name = sort sort_procs_by_name $p->all_procs;
my @by_pid  = sort sort_procs_by_pid  $p->all_procs;
my @by_uid  = sort sort_procs_by_uid  $p->all_procs;
# etc.

Each object returned by all_procs supports the following methods:

  • proc_name

  • proc_title

    The full command line with which the process was started.

  • pid

  • parent_pid

  • pgid

    Process ID of process group leader.

  • uid

  • euid

    Effective user ID.

  • gid

  • egid

    Effective group ID.

  • proc_size

    In bytes.

  • proc_resident

    In bytes.

  • time_spent

    Time running in seconds.

  • cpu_percent

  • nice

  • state

    One of SG_PROCESS_STATE_RUNNING, SG_PROCESS_STATE_SLEEPING, SG_PROCESS_STATE_STOPPED, SG_PROCESS_STATE_ZOMBIE and SG_PROCESS_STATE_UNKNOWN.

ERROR HANDLING

One function get_error exists that will return the error encountered during the last operation, if any. Its return value is dual-typed. In string context, it returns a text representation of the error. In numeric context it returns one of the following values:

SG_ERROR_ASPRINTF
SG_ERROR_DEVSTAT_GETDEVS
SG_ERROR_DEVSTAT_SELECTDEVS
SG_ERROR_ENOENT
SG_ERROR_GETIFADDRS
SG_ERROR_GETMNTINFO
SG_ERROR_GETPAGESIZE
SG_ERROR_KSTAT_DATA_LOOKUP
SG_ERROR_KSTAT_LOOKUP
SG_ERROR_KSTAT_OPEN
SG_ERROR_KSTAT_READ
SG_ERROR_KVM_GETSWAPINFO
SG_ERROR_KVM_OPENFILES
SG_ERROR_MALLOC
SG_ERROR_NONE
SG_ERROR_OPEN
SG_ERROR_OPENDIR
SG_ERROR_PARSE
SG_ERROR_SETEGID
SG_ERROR_SETEUID
SG_ERROR_SETMNTENT
SG_ERROR_SOCKET
SG_ERROR_SWAPCTL
SG_ERROR_SYSCONF
SG_ERROR_SYSCTL
SG_ERROR_SYSCTLBYNAME
SG_ERROR_SYSCTLNAMETOMIB
SG_ERROR_UNAME
SG_ERROR_UNSUPPORTED
SG_ERROR_XSW_VER_MISMATCH

Based on the above, you have finer control over the error handling:

    my $disks = get_disk_io_stats;
    
    if (! $disks) {
	if (get_error == SG_ERROR_PARSE) {
	    ...
	} else if (get_error == SG_ERROR_OPEN) {
	    ...
	} 
	etc. 
    }

EXPORT

All by default. This means all of the above functions plus the following constants:

SG_ERROR_ASPRINTF
SG_ERROR_DEVSTAT_GETDEVS
SG_ERROR_DEVSTAT_SELECTDEVS
SG_ERROR_ENOENT
SG_ERROR_GETIFADDRS
SG_ERROR_GETMNTINFO
SG_ERROR_GETPAGESIZE
SG_ERROR_KSTAT_DATA_LOOKUP
SG_ERROR_KSTAT_LOOKUP
SG_ERROR_KSTAT_OPEN
SG_ERROR_KSTAT_READ
SG_ERROR_KVM_GETSWAPINFO
SG_ERROR_KVM_OPENFILES
SG_ERROR_MALLOC
SG_ERROR_NONE
SG_ERROR_OPEN
SG_ERROR_OPENDIR
SG_ERROR_PARSE
SG_ERROR_SETEGID
SG_ERROR_SETEUID
SG_ERROR_SETMNTENT
SG_ERROR_SOCKET
SG_ERROR_SWAPCTL
SG_ERROR_SYSCONF
SG_ERROR_SYSCTL
SG_ERROR_SYSCTLBYNAME
SG_ERROR_SYSCTLNAMETOMIB
SG_ERROR_UNAME
SG_ERROR_UNSUPPORTED
SG_ERROR_XSW_VER_MISMATCH
SG_IFACE_DUPLEX_FULL
SG_IFACE_DUPLEX_HALF
SG_IFACE_DUPLEX_UNKNOWN
SG_PROCESS_STATE_RUNNING
SG_PROCESS_STATE_SLEEPING
SG_PROCESS_STATE_STOPPED
SG_PROCESS_STATE_UNKNOWN
SG_PROCESS_STATE_ZOMBIE

If you don't want that, use the module thusly:

use Unix::Statgrab ();

or provide a list of those symbols you want:

    use Unix::Statgrab qw/get_network_iface_stats 
                          SG_IFACE_DUPLEX_FULL
			  SG_IFACE_DUPLEX_HALF
			  SG_IFACE_DUPLEX_UNKNOWN/;

SEE ALSO

The excellent and very complete manpage of statgrab(3). You can get additional information for each of the above functions by prefixing the function name with "sg_" and feed it to man:

man sg_get_network_iface_stats

libstatgrab's home is at http://www.i-scream.org/libstatgrab/

AUTHOR

Tassilo von Parseval, <tassilo.von.parseval@rwth-aachen.de>

COPYRIGHT AND LICENSE

Copyright (C) 2004-2005 by Tassilo von Parseval

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.