View on
MetaCPAN
Tassilo von Parseval > Unix-Statgrab-0.04 > Unix::Statgrab

Download:
Unix-Statgrab-0.04.tar.gz

Dependencies

Annotate this POD (1)

CPAN RT

Open  0
View/Report Bugs
Module Version: 0.04   Source   Latest Release: Unix-Statgrab-0.111

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:

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:

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.

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:

get_load_stats()

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

get_mem_stats()

Returns statistics about memory usage. The following methods exist:

get_swap_stats()

Returns statistics about swap usage. The following methods exist:

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.

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.

get_page_stats()

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

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:

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:

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.

syntax highlighting: