Moving to New Domain

Hi, I have moved to a new domain where I will be posting new posts.
The URL is http://blog.sriunplugged.com
Check it Out.

Restoring the Grub after reinstalling Windows

After reinstalling windows or fixing MBR(Master Boot Record) you always loose your grub and you cannot boot to your linux. So this post is about the methods of restoring the grub. There are three methods I use. I will explain all three.

All three methods need a live cd of a linux. You need to boot from the live cd and take the terminal and do the following:

1. First method is using grub command. We initially go into the grub mode interface using the command
   
   sudo grub
   This will get you a "grub>" prompt (i.e. the grub shell). At grub>. enter these commands
   
   find /boot/grub/stage1
   If the find returned (hd0,1) then you would enter
   
   root (hd0,1)
   Now the root drive where the boot folder is mounted.Now we needed to setup the drive to boot to show the grub. We do this by
   
   setup (hd0)
   Finally exit the grub shell
   
   quit
   And then Reboot to and try if you are getting the grub.
   If not try the next method.
   
2. If couldn't get grub to find the stage1 file or even recognize the drive. Use this method.
   
   sudo mkdir /mnt/root
   
   sudo mount -t ext3 /dev/sda6 /mnt/root
   
   Then you have to mount the proc subsystem and udev inside /mnt/root also:
   
   
   sudo mount -t proc none /mnt/root/proc
   
   sudo mount -o bind /dev /mnt/root/dev
   
   Doing this allows grub to discover your drives. Next you have to chroot:
   
   
   sudo chroot /mnt/root /bin/bash
   
   Now that you're chrooted into your drive as root everything should work.
   
   
   sudo grub
   And then follow the 1st method to install the grub.
   
3. In lastest Linux you can use the command grub-install.The usage of this command is as
   
   sudo grub-install /dev/sda
   It might be hda if the hard disk is IDE and sda if disk is SATA.
   

So try it out the next time you loose your grub and tell me how it went.

Birthday Reminder For Gnome Panel

This program checks the file /home/rsrijith/shell/birthday_reminder.txt to find the upcoming birthdays in 20 days and writes into the file /home/rsrijith/shell/birthdays.
There is a file called /home/rsrijith/shell/birthdays1, the difference between it and birthdays file is that birthdays contains only first name of the person and birthdays1 contains the whole name.
So that's it. Now the code....

#!/bin/bash
echo "Birthday Finder ">>/home/rsrijith/logs/bday
date>>/home/rsrijith/logs/bday
tillm=$(date --date="+20 day" +"%b")
nowm=$(date +"%b")
tilld=$(date --date="+20 day" +"%2d")
nowd=$(date +"%d")
nowd=$((10#$nowd))
year=$(date +"%Y")
FileName='/home/rsrijith/shell/birthday_reminder.txt'
if [ -e /home/rsrijith/shell/birthdays ]
then
rm /home/rsrijith/shell/birthdays
fi
touch /home/rsrijith/shell/birthdays
if [ -e /home/rsrijith/shell/birthdays1 ]
then
rm /home/rsrijith/shell/birthdays1
fi
touch /home/rsrijith/shell/birthdays1
while read LINE
do
m=$(echo $LINE|cut -f2 -d',')
d=$(echo $LINE|cut -f3 -d',')
name=$(echo $LINE|cut -f1 -d',')
yob=$(echo $LINE|cut -f4 -d',')
if [ $m == $nowm ]
then
d="${d#0}";
if [ $nowd -le $d ]
then
name1=$name;
name=` echo $name|sed 's/\([^ ]*\).*/\1/;s/\([^.]*\).*/\1/'`
dif=$(($d-$nowd))
yrdif=$(($year-$yob))
if [ $dif -le 1 ]
then
if [ $dif -eq 0 ]
then
echo "Happy Birthday to "$name>>/home/rsrijith/shell/birthdays
echo "Happy Birthday to "$name1>>/home/rsrijith/shell/birthdays1
else
echo "$dif day to "$name"'s Birthday">>/home/rsrijith/shell/birthdays
echo "$dif day to "$name1"'s Birthday">>/home/rsrijith/shell/birthdays1
fi
else
echo "$dif days to "$name"'s Birthday">>/home/rsrijith/shell/birthdays
echo "$dif days to "$name1"'s Birthday">>/home/rsrijith/shell/birthdays1
fi

fi
else
if [ $m == $tillm ]
then
if [ $tilld -gt $d ]
then
name1=$name
name=` echo $name|sed 's/\([^ ]*\).*/\1/'`
lastdate=$(date -d "-$(date +%d) days +1 month"|cut -f 3 -d " ")
echo "$d $lastdate $nowd"

dif=$(($d+$lastdate-$nowd))
yrdif=$(($year-$yob))
echo "$dif days to "$name1"'s Birthday">>/home/rsrijith/shell/birthdays1
echo "$dif days to "$name"'s Birthday">>/home/rsrijith/shell/birthdays
fi
fi
fi
done < $FileName
if [ ! -s /home/rsrijith/shell/birthdays ]
then
echo "Nothing to Remind" > /home/rsrijith/shell/birthdays
fi
cat /home/rsrijith/shell/birthdays1|sort -n >/home/rsrijith/temp && mv /home/rsrijith/temp /home/rsrijith/shell/birthdays1
cat /home/rsrijith/shell/birthdays|sort -n >/home/rsrijith/temp && mv /home/rsrijith/temp /home/rsrijith/shell/birthdays

This code is part of the Perl Panel Code. The related codes to this are:

• Reminder for Gnome Panel
  
• Backend For Panel Reminder
  
• Auto Away Notifier for Pidgin in Perl

Reminder for Gnome Panel

This is the program that lets us to enter the text and time at which it should be reminded me. The command has the following options

• -d: date eg:  17/3/2009
  
• -t : time [ It's should be entered as 24hr clock] eg:   20:00:00
• -r : reminder text [ It should be entered in between a double quotes ] eg: "This is a test"
• -p :priority [ I hav'nt implemented it yet . Kept it for future implementation.] eg : 1
• -b :Remind me before [ By using it we can change the default remind before time of 5mins ie it is used to remind from a specific mins before the time we have scheduled to remind. It is specified in mins] eg: 5
  

#!/usr/bin/perl
use Time::Local;
my @date;
my @time;
my $d=0,$t=0,$r=0,$p=0,$b=0;
my @deftime=localtime();
$deftime[5]+=1900;
$deftime[4]++;
my $dv="$deftime[3]/$deftime[4]/$deftime[5]",$tv="$deftime[2]:$deftime[1]:$deftime[0]",$rv="",$pv=1,$bv=0;
foreach $argnum (0 .. $#ARGV)
{
if($ARGV[$argnum] eq "-d")
{
$d=1;
$dv=$ARGV[$argnum+1];
}
elsif($ARGV[$argnum] eq "-t")
{
$t=1;
$tv=$ARGV[$argnum+1];
}
elsif($ARGV[$argnum] eq "-r")
{
$r=1;
$rv=$ARGV[$argnum+1];
print "Remind Text:$rv\n";
}
elsif($ARGV[$argnum] eq "-p")
{
$p=1;
$pv=$ARGV[$argnum+1];
print "Priority:$pv\n";
}
elsif($ARGV[$argnum] eq "-b")
{
$b=1;
$bv=$ARGV[$argnum+1];
print "Remind Before:$bv\n";
}
}
@date=split('/',$dv);
print "Date:$dv\n";
@time={0,0,0};
@time=split(':',$tv);
print "Time:$tv";
$date[1]--;
my $time=timelocal($time[2],$time[1],$time[0],$date[0],$date[1],$date[2],);
my $nowtime=timelocal(localtime());
my $difftime=$time-$nowtime;
print "\nTime Of Alarm:".$time."\nTime Now:".$nowtime."\nDifference in Seconds:".$difftime."\n";

open (FH,">>/home/rsrijith/perl/reminder");
print FH "$time:$pv:$bv:$rv\n";
close FH;

This code is part of the Perl Panel Code. The related codes to this are:

• Backend For Panel Reminder
  
  
• Auto Away Notifier for Pidgin in Perl
  
  
• Birthday Reminder For Gnome Panel
  

Backend For Panel Reminder

I had already posted about creating a Display Reminders In Gnome Panel. This post is an addition to that script. This is a backend script that writes what to print into the panel_remind file. I use this script to print Birthday Reminder and Things to remember of which I will be posting shortly.
So the Code is simple Perl script.

#!/usr/bin/perl
our $printl;our $i=0;our $r=0;
$| = 1;
while(TRUE)
{
open (RB,"/home/rsrijith/perl/reminder");
my @line=<RB>;
close RB;
if($line[0])
{
while($line[$i])
{
open (WR,">/home/rsrijith/panel_remind");
my @s=split(":",$line[$i]);
my $nowtime=timelocal(localtime());
my $a=$s[2]+300;
if(($s[0]-$nowtime<=$a)&&($s[0]-$nowtime>=0))
{
my $t= to_int((($s[0]-$nowtime)/60));
while($t>0)
{
open (WR,">/home/rsrijith/panel_remind");
print WR "Red:In $t Mins - $s[3]";
close WR;
$r=1;
$t--;
sleep(60);
if( $t == 0)
{ `notify-send "$s[3]" -u critical -t 60000`}
}
}
open (WB,">/home/rsrijith/perl/reminder");
my $nowtime=timelocal(localtime());
if($s[0]-$nowtime>0)
{
print WB "$line[$i]";
close WB;
}
$i++;

}
if($r eq 0)
{
bday();
}
$i=0;
}
else
{
print "Birthday";
bday();
}
}


sub bday
{
open (RB,"/home/rsrijith/shell/birthdays");
my @line=<RB>;
close RB;

if((!$line[0])&&($r==0))
{
print "nothing to remind";
$printl="Black:Nothing to Remind \n:(";
open (WR,">/home/rsrijith/panel_remind");
print WR $printl;
close WR;
sleep(100);
}
while($line[$i])
{
$_=$line[$i];
if(m/Happy/)
{
$printl="Blue:$line[$i]";
}
else
{
$printl="Black:$line[$i]";
}
open (WR,">/home/rsrijith/panel_remind");
print WR $printl;
close WR;
$i++;
sleep(5);
}
$i=0;
return;
}

This script reads from files

• /home/rsrijith/shell/birthdays: The file contains birthdays of my friends that I need to be reminded of. The method to print the upcoming birthdays into this file is posted at <will be posted soon>.
  
• /home/rsrijith/perl/reminder:The file contains reminders that I need to  be reminded. I used another script to write into that file which is posted at <will be posted soon >.

This program needs libnotify  package. The package name is libnotify1 in my computer. It may vary with linux you are in.

• Reminder for Gnome Panel
  
  
• Auto Away Notifier for Pidgin in Perl
  
  
• Birthday Reminder For Gnome Panel
  

So the ordinary panel reminder can be made of some use using this script.
So try it out and tell me how it went.

Auto Away Notifier for Pidgin in Perl

Whenever I am away from laptop my chat buddies leave me lots message and finally lots of "You there???". So I thought of making a script that would inform my buddies that I am away when someone sends me a message.
This method works with Pigin API.
I have used /proc/acpi/button/lid/C267/state file to find if the lib of the laptop is closed or not. This file may vary in your laptop. So try to find the find the file in your computer that stores the status of the lid. It should be a file in /proc/acpi/button/lid/ folder and replace the file accordingly in your computer.
The Content of /proc/acpi/button/lid/C267/state is state: open and state: closed when the lid was closed.

We save this file as /usr/lib/purple-2/autonotifier.pl and use chmod +x /usr/lib/purple-2/test.pl to give the plugin execute permission. Now restart the Pidgin if it is running or open pidgin and go to Tools->Plugins and you should see a plugin named "Auto Away Plugin". Activate it and that's it.
I have used /sys/class/leds/b43-phy0\:\:radio/brightness file to notify me if there is any messages while i was away. It uses my Wi-fi light to notify me. When there is a message then the Wi-fi light blinks. This too is computer specific so find the file that controls any of the unused leds and replace that file too.

use Purple;
%PLUGIN_INFO = (
perl_api_version => 2,
name => "Auto Away Plugin",
version => "0.1",
summary => "Auto Away Notifier",
description => "Auto Away Notifier in Perl",
author => "R.Srijith <rsrijith007\@gmail.com",
url => "http://sriunplugged.blogspot.com",
load => "plugin_load",
unload => "plugin_unload"
);
sub plugin_init {
return %PLUGIN_INFO;
}

sub im_received {

my ($account, $sender, $message, $conv, $flags) = @_;
Purple::Debug::info("autonotify", "Message recieved\n");
$conv1 = Purple::Conversation->new(1, $account, $sender);
open FILE, ">>/home/rsrijith/logs/autonotifier.txt" or die $!;
open LID, "</proc/acpi/button/lid/C267/state" or die $!;
#$message=~s/<.*>//g;
while(<LID>)
{
if($_ =~ m/closed/)
{
print FILE "$sender:$message\n";
$im = $conv1->get_im_data();
if ($im) { print "ok.\n"; } else { print "fail.\n"; }
system('(if [ ! -e /var/lock/autoremind ]; then while grep -m 1 -q closed /proc/acpi/button/lid/C267/state; do touch /var/lock/autoremind; sleep 1; echo -n 0 >/sys/class/leds/b43-phy0\:\:radio/brightness; sleep 1;echo -n 1 >/sys/class/leds/b43-phy0\:\:radio/brightness; done; if [ -e /var/lock/autoremind ]; then rm /var/lock/autoremind; fi; fi)&');
$im->send("This is an automated response system: R Srijith is not at the desk rite now.");
}
}
close FILE;
}

sub plugin_load {
$plugin = shift;
$conversation_handle = Purple::Conversations::get_handle();
Purple::Signal::connect($conversation_handle, "received-im-msg", $plugin, \&im_received, $data);
Purple::Debug::info("autonotify", "Auto Notify Loaded\n");
}

sub plugin_unload {
Purple::Debug::info("autonotify", "Auto Notify Unloaded\n");
}

So try it out and comment me on how it went.

Display Reminders In Gnome Panel

 It was a long standing requirement of mine to create a reminder software or something which can keep me reminding of things as I always keep forgetting things. So I made a reminder that displays my reminders on the Gnome Panel.
It looks something like this:

So how do we do it?

1st of all we need to display the program we need in the Add to Panel.

For that we add to the bonobo server list. We do this by adding the following code in the folder  /usr/lib/bonobo/servers/. Let us name the file as GNOME_PerlApplet.server
The content of this file should be :

<oaf_info>
  <oaf_server iid="OAFIID:PerlSampleApplet_Factory" type="exe" location="/home/rsrijith/perl/panel-applet">
    <oaf_attribute name="repo_ids" type="stringv">
      <item value="IDL:Bonobo/GenericFactory:1.0"/>
      <item value="IDL:Bonobo/Unknown:1.0"/>
    </oaf_attribute>
    <oaf_attribute name="name" type="string" value="Panel Reminder"/>
    <oaf_attribute name="description" type="string" value="Perl Program working in Panel"/>
  </oaf_server>

  <oaf_server iid="OAFIID:PerlSampleApplet" type="factory" location="OAFIID:PerlSampleApplet_Factory">
    <oaf_attribute name="repo_ids" type="stringv">
      <item value="IDL:GNOME/Vertigo/PanelAppletShell:1.0"/>
      <item value="IDL:Bonobo/Control:1.0"/>
      <item value="IDL:Bonobo/Unknown:1.0"/>
    </oaf_attribute>
    <oaf_attribute name="name" type="string" value="Panel Reminder"/>
    <oaf_attribute name="description" type="string" value="Perl Program working in Panel:R Srijith"/>
    <oaf_attribute name="panel:category" type="string" value="Amusements"/>
    <oaf_attribute name="panel:icon" type="string" value="bug-buddy.png"/>
  </oaf_server>
</oaf_info>

So this specifies the location of the perl file to run on adding this applet. So here it is /home/rsrijith/perl/panel-applet . This file should print the reminders to be printed on the panel.
The program need the Following packages:

Perl packages:

• ExtUtils::Depends

• ExtUtils::PkgConfig

• Gnome2::GConf
  

• Gnome2::PanelApplet

You install this using

sudo perl -MCPAN -e 'install <package-name>'

Linux Package:

• libpanelappletmm-2.6-1c2
• libpanelappletmm-2.6-dev

You install this using

sudo apt-get install <package-name>

Thus the perl file content is :

#!/usr/bin/perl -w

use warnings;
use utf8;
use Gnome2::PanelApplet;
Gnome2::Program->init ('A Stupid Applet Written in Perl', '0.01', 'libgnomeui',
                       sm_connect => FALSE);

Gnome2::PanelApplet::Factory->main ('OAFIID:PerlSampleApplet_Factory',
                                    'Gnome2::PanelApplet',
                                    \&fill);


sub fill {
  my ($applet, $iid, $data) = @_;

  if ($iid ne 'OAFIID:PerlSampleApplet') {
    return FALSE;
  }
 
  my $menu_xml = <<EOX;
<popup name="button3">
  <menuitem name="Properties Item"
            verb="Birthdays"
            _label="Birthdays"
        pixtype="stock"
        pixname="gtk-properties"/>
  <menuitem name="DesktopSwitcher Item"
        verb="DesktopSwitcher"
        _label="Wallpaper Switcher"
        pixtype="stock"
        pixname="gtk-stock"/>
    <menuitem name="Walldelete Item"
        verb="Walldelete"
        _label="Wallpaper Delete"
        pixtype="stock"
        pixname="gtk-stock"/>              
  <menuitem name="About Item"
        verb="About"
        _label="About"
        pixtype="stock"
        pixname="gnome-stock-about"/>
</popup>
EOX

  my $cb_mapping = {
    Birthdays => [\&properties_callback, 'default!'],
    DesktopSwitcher => \&deskswitcher_callback,
    Walldelete => \&walldelete_callback,
    About => \&about_callback,
  };

  $applet->setup_menu($menu_xml, $cb_mapping, 'default?');
  our $i=0;our @line;

  our $label = Gtk2::Label->new;
  $label->set_justify("left");
    $label->set_line_wrap(TRUE);
    $label->modify_font(Gtk2::Pango::FontDescription->from_string("Monospace 10"));
    $label->modify_fg("normal", Gtk2::Gdk::Color->parse("Black"));
  $applet->add ($label);
  $applet->show_all;
 
 Glib::Timeout->add (5000, \&update_value);
 #Glib::Timeout->add (500, \&update_list);
 sub update_list{
 open FILE,"/home/rsrijith/panel_remind";
  @line=<FILE>;
  close FILE;
 }
 sub update_value
 {
 
  my @string=split(':',$line[0]);
  $label->modify_fg("normal", Gtk2::Gdk::Color->parse($string[0]));
  $label->set_markup("\n".$string[1]);
  update_list();
 }
}

sub deskswitcher_callback
{
 system('/home/rsrijith/shell/deskback 2>>/home/rsrijith/logs/desktopbackground');
}

sub walldelete_callback
{
 system('/home/rsrijith/shell/deletewall 2>>/home/rsrijith/logs/desktopbackground');
}

sub properties_callback {
    my $b="";
        open BDAY,"/home/rsrijith/shell/birthdays1";
    while(<BDAY>)
    { $b.=$_."\n";
    }
  my $dialog = Gtk2::MessageDialog->new (undef, [],
                                         'info', 'ok',
                                         $b);
  $dialog->run;
  $dialog->destroy;
}


sub about_callback {
  my $about = Gnome2::About->new ('Panel Reminder', '0.1',
                                  'Perl Program working in Panel',
                                  '© 2009 R.Srijith',
                                  'R.Srijith <rsrijith007@gmail.com');
  $about->show;
}

This program prints the contents of /home/rsrijith/panel_remind
An Example of the content of that file should be as

Blue:Happy Birthday to Mahima

So that's it!! And Happy Birthday Mahima.

• Reminder for Gnome Panel
  
  
• Backend For Panel Reminder
  
  
• Birthday Reminder For Gnome Panel
  

Comment me if you have any doubts or if it's not working.

BSNL Dataone Auto Downloader

Bsnl(India) provides an account that has 2am to 8am unlimited download. It was not easy to wake up at 2am and switch on the computer and sleep again. So I tried to find a method to switch on the computer automatically at 2am and download and shutdown at 8am. Although the I thought the idea was foolish, I found out that there actually is a method for doing it. "ACPI Alarm" was introduced in 1999 or so (Even my old PC had it).

So what does this alarm do? The ACPI alarm wakes up the computer from shutdown or hibernate. You need to keep the UPS or Power Plug to the CPU on after scheduling the time in ACPI or it gets reseted.

This function needs Bios Support and I feel most bios supports this feature.
The method to do this depends on your kernel version.
So check the Kernel Version first using the command.

uname -r

If Kernel > 2.6.22 and higher use /sys/class/rtc/rtc0/wakealarm

Kernel < 2.6.21 and lower use /proc/acpi/alarm

Disable hwclock updates

On most machines it's required to make a small change to the Linux shutdown procedure. When your machine goes down, most linux distributions write the system time/data back to the bios. On MANY machines the machines never wakes-up after a time/data update. It's recommended to make this change before you start. See below for more details (distro specific),

The reason for the recommendation above is that most linux distributions write the current system time back to the bios when shutting down the machine, and with some BIOSes, the machine will not wake up if the hardware clock is modified after the alarm timer has been set. To avoid that, it is necessary to disable the writing of the current system time to the hardware clock in the system shutdown scripts. This is distribution specific, so here are some examples:

Debian (and Ubuntu)

modifying

/etc/default/rcS

with the following will fix this problem:

/etc/default/rcS

#
# /etc/default/rcS
#
# Default settings for the scripts in /etc/rcS.d/
#
# For information about these variables see the rcS(5) manual page.
#
# This file belongs to the "initscripts" package.

TMPTIME=0
SULOGIN=no
DELAYLOGIN=no
UTC=no
VERBOSE=no
FSCKFIX=no
==> HWCLOCKACCESS=no

Gentoo Set clock_systohc to "NO" in

/etc/conf.d/clock

:

/etc/conf.d/clock

# Set CLOCK to "UTC" if your system clock is set to UTC (also known as
# Greenwich Mean Time).  If your clock is set to the local time, then
# set CLOCK to "local".  Note that if you dual boot with Windows, then
# you should set it to "local".
clock="UTC"

# If you want to set the Hardware Clock to the current System Time
# during shutdown, then say "YES" here.
# You normally don't need to do this if you run a ntp daemon.
clock_systohc="NO"

# If you wish to pass any other arguments to hwclock during bootup,
# you may do so here. Alpha users may wish to use --arc or --srm here.
clock_args=""

openSUSE

modifying

/etc/sysconfig/clock

holds a switch to write back system time to the hardware clock

/etc/sysconfig/clock

# Set to "-u" if your system clock is set to UTC, and to "--localtime"
# if your clock runs that way.
#
HWCLOCK="-u"

SYSTOHC="no"
# Is set to "yes" write back the system time to the hardware
# clock at reboot or shutdown. Usefull if hardware clock is
# much more inaccurate than system clock.  Set to "no" if
# system time does it wrong due e.g. missed timer interrupts.
# If set to "no" the hardware clock adjust feature is also
# skipped because it is rather useless without writing back
# the system time to the hardware clock.
               

Fedora Core 6

modifying

/etc/init.d/halt

with the following will fix this problem:

/etc/init.d/halt

==>  ACPITIME=`cat /proc/acpi/alarm`

     [ -x /sbin/hwclock ] && action $"Syncing hardware clock to system time" /sbin/hwclock $CLOCKFLAGS
                
==>  echo "$ACPITIME" > /proc/acpi/alarm  

Using /proc/acpi/alarm for Kernel 2.6.21 and lower

Check that you can write a new time to the RTC Clock Alarm (you will need to be Root) Format is YYYY-MM-DD HH:MM:SS

echo "2009-02-1 02:00:00" > /proc/acpi/alarm

Using /sys/class/rtc/rtc0/wakealarm

Beginning with kernel 2.6.22 /proc/acpi/alarm has been removed and replaced with /sys/class/rtc/rtc0/wakealarm. The key differences with the wakealarm interface are:

1. Instead of accepting a formatted time, wakealarm accepts the number of seconds since Jan 1, 1970.
2. If you want to change the wakealarm time, you first need to reset the time.
3. You have to make sure that your bios clock is set to UTC time not localtime otherwise it will wakeup at the wrong time. None the less it is still possible if the bios clock is set to localtime (likely if you also run windows), see the section below for how to set the alarm correctly when the bios clock is in localtime.

An example of setting alarm is as follows

echo 0 > /sys/class/rtc/rtc0/wakealarm
date -u --date "Jul 1, 2008 10:32:00" +%s > /sys/class/rtc/rtc0/wakealarm

Then we can confirm that the alarm is set with the following.

cat /proc/driver/rtc

If the alarm is set then you should see something like this. If so then shutdown and see if it wakes up at the alarm date/time.

rtc_time : 13:40:26
rtc_date : 2008-12-21
alrm_time : 10:45:00
alrm_date : 2008-12-22
alarm_IRQ : yes
alrm_pending : no
24hr : yes
periodic_IRQ : no
update_IRQ : no
HPET_emulated : no
DST_enable : no
periodic_freq : 1024
batt_status : okay

If you see the alarm date similar to ****-12-21 then the alarm is set to a time in the past and it won't wake up.

rtc_time : 13:42:01
rtc_date : 2008-12-21
alrm_time : 13:46:59
alrm_date : ****-12-21
alarm_IRQ : no
alrm_pending : no
24hr : yes
periodic_IRQ : no
update_IRQ : no
HPET_emulated : no
DST_enable : no
periodic_freq : 1024
batt_status : okay

In most systems this method should work. But in some Bios called as Fussy Bios using this function is tough. Lets see the different problems it might have and it's solution

1. Disable/Enable RTC in BIOS
   
   In some cases you need to disable the RTC alarm function is the bios to make things work.
   
   * Another possible glitch is, that the option 'Resume By Alarm' (or whatever it is called) is set to Enabled but wake up using /proc/acpi/alarm only works if the option is set to Disabled. Sounds weird but works with some boards.
   * On many boards, when the RTC setting is enabled in the BIOS, it will wake only from a time set and saved from BIOS setup, and not from a time set outside of the BIOS setup environment - as we want. All of the boards the original author of this document needed this setting disabled to correctly wake with ACPI. This is the recommended starting point.
2. Time/Date not visible in BIOS
   
   After you have set the RTC alarm from Linux, it could be that you not see changes in the BIOS but it still works.
3. Required to write time/date two times
   
   Some users reported that their BIOS is only updated after writing 2 times to the alarm file. (reported with proc/acpi/alarm)

Ok, so the Basic of ACPI is done.Now lets see how we switch on the computer at 2am.
We use the command as,

• If it's to be set on the next day 2pm :
  
  date +'%a %b %d 02:00:00 GMT %Y' -d '+1 day'|xargs -i date '+%s' -d''{}'' > /sys/class/rtc/rtc0/wakealarm
• If it's to be set on the same day 2pm :
  
  date +'%a %b %d 02:00:00 GMT %Y' |xargs -i date '+%s' -d''{}'' > /sys/class/rtc/rtc0/wakealarm

So, the computer boots up at 2am. Now we need to reboot the modem.
Rebooting modem is required as Dataone calculates session from On time to Off time. If the modem is up from 1am to 5am and we download 4gb, what the dataone does is, it takes the total time modem was on ie 4 hours. 2am to 5am is free so the non free time is 1hr so we will be charged for 1gb (4gb/4 hours). So it's essential to reboot the modem at 2am.
The code to reboot is ,

#!/bin/bash
now=$(date +"%H")
now=${now#0};
if (( $now < 8 )) && (( $now > 1 ))
then
(echo "admin";
sleep 1;
echo "admin";
sleep 1;
echo "13";
sleep 1;
echo "1";
sleep 40;
)|telnet 192.168.1.1
deluge &
fi

deluge is torrent client I use.
We should run this command in sessions so that it runs at each boot.
We do this by Adding in
System -> Preferences -> Sessions -> Add
Give the path of the File that contains the above script. That's it!! Done!!. The script starts at 2am. Now we need to stop the script at 8am.
We use following code for that,

#!/bin/bash
now=$(date +"%H")
date +'%a %b %d 02:00:00 GMT %Y' -d '+1 day'|xargs -i date '+%s' -d''{}'' > /sys/class/rtc/rtc0/wakealarm
sudo killall deluge
sleep 5;
(echo "admin";
sleep 1;
echo "admin";
sleep 1;
echo "13";
sleep 1;
echo "1";
sleep 40;
)|telnet 192.168.1.1
sudo shutdown -h now

We use the crontab to schedule and run it at 7 59am. If you are not sure how to write a crontab entry see the posts before.
Well Happy Downloading!! Keep me Posted on how it went.