NAME

       Linux::KernelSort - Perl extension for sorting and comparing Linux kernel versions.  The
       expected kernel version naming convention is the same naming convetion demonstrated by
       http://www.kernel.org.  NOTE:  Currently, only the 2.6.x series of kernels (including
       -rc's, -git's, and -mm's) are properly evaluated.

SYNOPSIS

         use Linux::KernelSort;
         my $kernel = new Linux::KernelSort;

         my $ret;
         my $version1 = "2.6.19";
         my $version2 = "2.6.19-rc2-git7";
         $ret = $kernel->compare($version1, $version2);

         if ($ret == 0) {
           print "$version1 and $version2 are the same version\n";
         } elsif ($ret > 0) {
           print "$version1 is newer than $version2\n";
         } else {
           print "$version1 is older than $version2\n";
         }

         my @kernel_list = ( '2.6.15',
                             '2.6.18',
                             '2.6.18-rc2',
                             '2.6.18-rc2-git2',
                             '2.6.18-mm1',
                             '2.6.18-rc2-mm1' );

         my @sorted_list = $kernel->sort(@kernel_list);

         print join( ', ', @sorted_list );

DESCRIPTION

       Linux::KernelSort is intended to sort a list of kernel versions into ascending order.  It
       also provides the capability to compare two kernel versions and determine if one version
       is newer, older, or the same as the other version.

FUNCTIONS

   version_check() Purpose:  Verify the version is valid and follows the proper naming convention
       demonstrated by http://www.kernel.org Input:    A string containing the kernel version
       Return:   0 if version is valid 1 if version is invalid
   rank()
           Purpose:  Generate a ranking for a given kernel version
           Input:    A string containing the kernel version which
                     follows the proper naming convention demonstrated
                     by http://www.kernel.org
           Return:   Kernel ranking

   compare()
           Purpose:  Compare two kernel versions
           Input:    Strings ($kernel1, $kernel2) each containing a
                     kernel version which follows the proper naming
                     conventaion demonstrated by http://www.kernel.org
           Return   -1 if $kernel1 < $kernel2  (ie $kernel1 is older than $kernel2)
                     0 if $kernel1 == $kernel2 (ie $kernel1 is the same version as $kernel2)
                     1 if $kernel1 > $kernel2  (ie $kernel1 is newer than $kernel2)

   sort()
           Purpose:  Sort a list of kernel versions in ascending order.
                     Uses shell sort algorithm.
           Input:    Array of strings containing kernel versions which
                     follows the proper naming convention demonstrated
                     by http://www.kernel.org
           Return:   Sorted array

AUTHOR

       Leann Ogasawara <lt>ogasawara@osdl.org<gt>

COPYRIGHT AND LICENSE

       Linux-KernelSort is Copyright (c) 2006, by Leann Ogasawara.  All rights reserved. You may
       distribute this code under the terms of either the GNU General Public License or the
       Artistic License, as specified in the Perl README file.