small-hacks/merge-bash-histories.plx

#!/usr/bin/perl
# Copyright (C) 2010, Bradley M. Kuhn
#
# This program gives you software freedom; you can copy, modify, convey,
# and/or redistribute it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program in a file called 'GPLv3'.  If not, write to the:
#    Free Software Foundation, Inc., 51 Franklin St, Fifth Floor
#                                    Boston, MA 02110-1301, USA.

use strict;
use warnings;

my %history;
my $time;
while (my $line = <>) {
  chomp $line;
  if ($line =~ /^#\s*(\d+)/) {
    $time = $1;
  } else {
    $history{$time} = {} if not defined $history{$time};
    $history{$time}{$line} = 1;
  }
}

foreach my $key (sort { $a <=> $b } keys %history) {
  foreach my $cmd (sort {$a cmp $b } keys %{$history{$key}}) {
    print "#$key\n$cmd\n";
  }
}