Save 90% on international calls and sms with Vopium

March 15, 2010 3 comments

If you are living abroad or frequently call your family and friends abroad you can save upto 90% on international calls and sms with Vopium, a Copenhagen – Denmark based company. VopiumVopium provides it’s users variety of simple ways to make international calls and sms via it’s web portal and mobile application, Vopium is a mobile phone application supported on variety of platforms (symbian, iphone, android, java).

Apart from international calls and sms plans, Vopium enables it’s users to talk and chat using Skype, Google Talk, Msn and Yahoo.

Currently Vopium is available in 18 countries including Australia, Belgium, Denmark, France, Finland, Germany, Netherlands, Italy, Norway, Spain, Switzerland, Sweden, UK & USA.

To find out more and get started with Vopium, visit vopium.com

howto install Karaka: xmpp gateway to skype!

July 16, 2009 2 comments

You came here searching for howto install karaka. Vipdia Limited doesn’t tell much on how to setup karaka step by step, yesterday someone asked this question on karaka-discuss mailing list, this post is helpful for you if you are thinking about giving karaka a try.

more here: http://groups.google.com/group/karaka-discuss/browse_thread/thread/d6eb8fcd61bd3e05

update and retrieve twitter timeline from linux shell

January 24, 2009 8 comments

you can update your twitter status and follow feeds using linux shell, this is a quick tip for linux lover’s, this is the reason i prefer linux over other operating systems is it’s total usefullnes,

to post your status on twitter type:

curl -s -u username:password -d status="your_status_message goes here" http://twitter.com/statuses/update.xml > /dev/null

replace username, password and message to post with the your own.

to follow feeds from twitter.

curl -s -u username:password http://twitter.com/statuses/friends_timeline.rss | grep title | sed -e 's/]*>//g'

replace username and password with your own. above command will retrieve recent rss entries from your twitter timeline.

one more cool thing you can do with this long command is to enclose it put it in a text file, let’s say “/usr/local/bin/get-twits” and make it exectuable by issuing

chmod a+x /usr/local/bin/get-twits

now open a new terminal windows and type:  watch --interval=60 get-twits

this command will keep your terminal windows updated with recent twitter updates.

enjoy 🙂

cloning harddrives over network

December 30, 2008 6 comments

To clone identical drives in a linux system you can use dd command, dd command makes it really easy.

dd if=/dev/hda of=/dev/hdb

above command will clone hda to hdb (partitions, boot record etc), but what if you have to clone a drive that is not attached to same system?

I found a really interesting way to transfer files over the network simple by using netcat and dd.

  • Boot the machine (where second drive is attached) with a live cd distro like Ubuntu or Knoppix. Setup networking or let the DHCP server assign an ip automatically. My DHCP assigned this machine ip 192.168.0.21
  • run following command on this machine
    nc -l -p 7777 | dd of=/dev/hdb
    (where /dev/hdb is the target drive)
  • Now come to the machine where you have attached the drive to be cloned and issue following command.
    dd if=/dev/hda | nc 192.168.0.21 7777
    (/dev/hda is the drive to be cloned)

It will take time (usually several hours) depending on size of the drive. If you are worried about bandwidth you can pipe through gzip to compress and uncompress the streamed data on source and destination machine respectively, to do this you would run following commands.

On target machine:

nc -l -p 7777 | gzip –dfc | dd of=/dev/hdb

And on source machine.

dd if=/dev/hda | gzip –cf | nc 192.168.0.21 7777

have fun with dd and nc 🙂

Categories: linux, ubuntu Tags: , , ,

asterisk 1.2 with realtime ldap driver

December 28, 2008 13 comments

I have created an auto install script based on http://www.cahilig.org/install-asterisk-12-auto-install-script-centos-4-and-centos-5 to install Asterisk 1.2 with ldap realtime driver support (modified original script to enable realtime ldap support).

This script should work almost with any(Redhat, Centos, Mandrake, Debian, Slackware) Linux distro

Before running this script you must install following packages.

For Centos, Redhat:

yum install openldap-devel gcc kernel-devel bison openssl-devel libtermcap-devel ncurses-devel

For Debian, Ubuntu:

apt-get install libldap2-dev build-essential linux-headers-`uname -r` libncurses5-dev libssl-dev

You can download the script from here, simply run the script to start installation process.

download Asterisk schema for OpenLdap here

Installer and installation process is not tested, if you find any problem please let me know.

#!/bin/sh
#Asterisk Download page
ZAPTEL="http://downloads.digium.com/pub/zaptel/releases/zaptel-1.2.9.tar.gz"
ASTERISK="http://downloads.digium.com/pub/asterisk/releases/asterisk-1.2.30.tar.gz"
ASTERISKADDONS="http://downloads.digium.com/pub/asterisk/releases/asterisk-addons-1.2.9.tar.gz"
RTLDAP="http://free.oxymium.net/Asterisk/res_config_ldap.tgz"
RTLDAPPATCH="http://mustafa.pk.googlepages.com/res_config_ldap.c.patch"
CONFIGPATCH="http://mustafa.pk.googlepages.com/config.c.patch"
MAKEFILEPATCH="http://mustafa.pk.googlepages.com/resmkfile.patch"
#Asterisk Package
ZAPPACKAGE="zaptel-1.2.9.tar.gz"
ASTPACKAGE="asterisk-1.2.30.tar.gz"
ASTADDONSPACKAGE="asterisk-addons-1.2.9.tar.gz"
#Asterisk Folder
ZAPFOLDER="zaptel-1.2.9"
ASTFOLDER="asterisk-1.2.30"
ASTADDONSFOLDER="asterisk-addons-1.2.9"
REALTIMEDIRVER="res_config_ldap.tgz"
if [ -f /etc/redhat-release ] ; then
DISTRO="redhat"
elif [ -f /etc/debian_version ] ; then
DISTRO="debian"
elif [ -f /etc/SUSE-release ] ; then
DISTRO="redhat"
elif [ -f /etc/mandrake-release ] ; then
DISTRO="mandrake"
elif [ -f /etc/slackware-release ] ; then
DISTRO="slackware"
elif [ -f /etc/gentoo-release ] ; then
DISTRO="gentoo"
fi

echo "Downloading and extracting zaptel and asterisk source"
cd /usr/local/src/
if [ ! -e $ZAPPACKAGE ]; then
  wget $ZAPTEL
fi
if [ ! -e $ASTPACKAGE ]; then
  wget $ASTERISK
fi
if [ ! -e $ASTADDONSPACKAGE ]; then
  wget $ASTERISKADDONS
fi
tar -zvxf $ZAPPACKAGE
tar -zvxf $ASTPACKAGE
tar -zvxf $ASTADDONSPACKAGE 

echo "Installing zaptel"
cd $ZAPFOLDER
make clean
make
make install
cd ..

echo "Installing asterisk"
cd $ASTFOLDER
echo "Downloading patches"
wget $CONFIGPATCH
wget $MAKEFILEPATCH
patch -p0<resmkfile.patch
patch -p0<config.c.patch
echo "Downloading Realtime Ldap driver"
cd res
wget $RTLDAP
tar -zxvf $REALTIMEDIRVER
wget $RTLDAPPATCH
patch -p0<res_config_ldap.c.patch
cd ../configs
wget http://mustafa.pk.googlepages.com/extconfig.conf.sample
wget http://mustafa.pk.googlepages.com/res_ldap.conf.sample
cd ..
make clean
make
make install
make samples
cp contrib/init.d/rc.$DISTRO.asterisk /etc/init.d/asterisk
cd ..

echo "Installing asterisk-addons"
cd $ASTADDONSFOLDER
make clean
make
make install

echo "Loading ztdummy driver"
modprobe zaptel
modprobe ztdummy

echo "adding rules to /etc/rc.local"

echo "modprobe zaptel
modprobe ztdummy
" >> /etc/rc.local

echo "Downloading open source g729 codec"
cd /usr/lib/asterisk/modules/
wget http://asterisk.hosting.lv/bin12/codec_g729-ast12-gcc4-glibc-pentium4.so

echo "Running Asterisk"
/etc/init.d/asterisk start

echo "***********************************************************************"
echo "*             INSTALLATION SUCCESSFUL                                 *"
echo "***********************************************************************"
echo "* You can test if Asterisk installed successfully using               *"
echo "* asterisk -ncrvvv and start configuring your dial plan               *"
echo "***********************************************************************"
exit

“kill -9” song by monzy

December 27, 2008 1 comment

really funny rap song about “kill -9” command by Monzy at stanford university.

check it out: audio, video, lyrics

Categories: linux, videos Tags: , ,

evolution of a programmer

December 15, 2008 4 comments

High School/Junior High

  10 PRINT "HELLO WORLD"
  20 END

First year in College

  program Hello(input, output)
    begin
      writeln('Hello World')
    end.

Senior year in College

  (defun hello
    (print
      (cons 'Hello (list 'World))))

New professional

  #include
  void main(void)
  {
    char *message[] = {"Hello ", "World"};
    int i;

    for(i = 0; i < 2; ++i)
      printf("%s", message[i]);
    printf("\n");
  }

Seasoned professional

  #include
  #include 

  class string
  {
  private:
    int size;
    char *ptr;

  public:
    string() : size(0), ptr(new char('')) {}

    string(const string &s) : size(s.size)
    {
      ptr = new char[size + 1];
      strcpy(ptr, s.ptr);
    }

    ~string()
    {
      delete [] ptr;
    }

    friend ostream &operator <<(ostream &, const string &);
    string &operator=(const char *);
  };

  ostream &operator<<(ostream &stream, const string &s)
  {
    return(stream << s.ptr);
  }

  string &string::operator=(const char *chrs)
  {
    if (this != &chrs)
    {
      delete [] ptr;
     size = strlen(chrs);
      ptr = new char[size + 1];
      strcpy(ptr, chrs);
    }
    return(*this);
  }

  int main()
  {
    string str;

    str = "Hello World";
    cout << str << endl;

    return(0);
  }

Master Programmer

  [
  uuid(2573F8F4-CFEE-101A-9A9F-00AA00342820)
  ]
  library LHello
  {
      // bring in the master library
      importlib("actimp.tlb");
      importlib("actexp.tlb");

      // bring in my interfaces
      #include "pshlo.idl"

      [
      uuid(2573F8F5-CFEE-101A-9A9F-00AA00342820)
      ]
      cotype THello
   {
   interface IHello;
   interface IPersistFile;
   };
  };

  [
  exe,
  uuid(2573F890-CFEE-101A-9A9F-00AA00342820)
  ]
  module CHelloLib
  {

      // some code related header files
      importheader();
      importheader();
      importheader();
      importheader("pshlo.h");
      importheader("shlo.hxx");
      importheader("mycls.hxx");

      // needed typelibs
      importlib("actimp.tlb");
      importlib("actexp.tlb");
      importlib("thlo.tlb");

      [
      uuid(2573F891-CFEE-101A-9A9F-00AA00342820),
      aggregatable
      ]
      coclass CHello
   {
   cotype THello;
   };
  };

  #include "ipfix.hxx"

  extern HANDLE hEvent;

  class CHello : public CHelloBase
  {
  public:
      IPFIX(CLSID_CHello);

      CHello(IUnknown *pUnk);
      ~CHello();

      HRESULT  __stdcall PrintSz(LPWSTR pwszString);

  private:
      static int cObjRef;
  };

  #include
  #include
  #include
  #include
  #include "thlo.h"
  #include "pshlo.h"
  #include "shlo.hxx"
  #include "mycls.hxx"

  int CHello::cObjRef = 0;

  CHello::CHello(IUnknown *pUnk) : CHelloBase(pUnk)
  {
      cObjRef++;
      return;
  }

  HRESULT  __stdcall  CHello::PrintSz(LPWSTR pwszString)
  {
      printf("%ws\n", pwszString);
      return(ResultFromScode(S_OK));
  }

  CHello::~CHello(void)
  {

  // when the object count goes to zero, stop the server
  cObjRef--;
  if( cObjRef == 0 )
      PulseEvent(hEvent);

  return;
  }

  #include
  #include
  #include "pshlo.h"
  #include "shlo.hxx"
  #include "mycls.hxx"

  HANDLE hEvent;

   int _cdecl main(
  int argc,
  char * argv[]
  ) {
  ULONG ulRef;
  DWORD dwRegistration;
  CHelloCF *pCF = new CHelloCF();

  hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);

  // Initialize the OLE libraries
  CoInitializeEx(NULL, COINIT_MULTITHREADED);

  CoRegisterClassObject(CLSID_CHello, pCF, CLSCTX_LOCAL_SERVER,
      REGCLS_MULTIPLEUSE, &dwRegistration);

  // wait on an event to stop
  WaitForSingleObject(hEvent, INFINITE);

  // revoke and release the class object
  CoRevokeClassObject(dwRegistration);
  ulRef = pCF->Release();

  // Tell OLE we are going away.
  CoUninitialize();

  return(0); }

  extern CLSID CLSID_CHello;
  extern UUID LIBID_CHelloLib;

  CLSID CLSID_CHello = { /* 2573F891-CFEE-101A-9A9F-00AA00342820 */
      0x2573F891,
      0xCFEE,
      0x101A,
      { 0x9A, 0x9F, 0x00, 0xAA, 0x00, 0x34, 0x28, 0x20 }
  };

  UUID LIBID_CHelloLib = { /* 2573F890-CFEE-101A-9A9F-00AA00342820 */
      0x2573F890,
      0xCFEE,
      0x101A,
      { 0x9A, 0x9F, 0x00, 0xAA, 0x00, 0x34, 0x28, 0x20 }
  };

  #include
  #include
  #include
  #include
  #include
  #include "pshlo.h"
  #include "shlo.hxx"
  #include "clsid.h"

  int _cdecl main(
  int argc,
  char * argv[]
  ) {
  HRESULT  hRslt;
  IHello        *pHello;
  ULONG  ulCnt;
  IMoniker * pmk;
  WCHAR  wcsT[_MAX_PATH];
  WCHAR  wcsPath[2 * _MAX_PATH];

  // get object path
  wcsPath[0] = '';
  wcsT[0] = '';
  if( argc > 1) {
      mbstowcs(wcsPath, argv[1], strlen(argv[1]) + 1);
      wcsupr(wcsPath);
      }
  else {
      fprintf(stderr, "Object path must be specified\n");
      return(1);
      }

  // get print string
  if(argc > 2)
      mbstowcs(wcsT, argv[2], strlen(argv[2]) + 1);
  else
      wcscpy(wcsT, L"Hello World");

  printf("Linking to object %ws\n", wcsPath);
  printf("Text String %ws\n", wcsT);

  // Initialize the OLE libraries
  hRslt = CoInitializeEx(NULL, COINIT_MULTITHREADED);

  if(SUCCEEDED(hRslt)) {

      hRslt = CreateFileMoniker(wcsPath, &pmk);
      if(SUCCEEDED(hRslt))
   hRslt = BindMoniker(pmk, 0, IID_IHello, (void **)&pHello);

      if(SUCCEEDED(hRslt)) {

   // print a string out
   pHello->PrintSz(wcsT);

   Sleep(2000);
   ulCnt = pHello->Release();
   }
      else
   printf("Failure to connect, status: %lx", hRslt);

      // Tell OLE we are going away.
      CoUninitialize();
      }

  return(0);
  }

Apprentice Hacker

  #!/usr/local/bin/perl
  $msg="Hello, world.\n";
  if ($#ARGV >= 0) {
    while(defined($arg=shift(@ARGV))) {
      $outfilename = $arg;
      open(FILE, ">" . $outfilename) || die "Can't write $arg: $!\n";
      print (FILE $msg);
      close(FILE) || die "Can't close $arg: $!\n";
    }
  } else {
    print ($msg);
  }
  1;

Experienced Hacker

  #include
  #define S "Hello, World\n"
  main(){exit(printf(S) == strlen(S) ? 0 : 1);}

Seasoned Hacker

  % cc -o a.out ~/src/misc/hw/hw.c
  % a.out

Guru Hacker

  % cat
  Hello, world.
  ^D

New Manager

  10 PRINT "HELLO WORLD"
  20 END

Middle Manager

  mail -s "Hello, world." bob@b12
  Bob, could you please write me a program that prints "Hello,
 world."?
  I need it by tomorrow.
  ^D

Senior Manager

  % zmail jim
  I need a "Hello, world." program by this afternoon.

Chief Executive

  % letter
  letter: Command not found.
  % mail
  To: ^X ^F ^C
  % help mail
  help: Command not found.
  % damn!
  !: Event unrecognized
  % logout
Categories: Uncategorized Tags: ,

encouraging FOSS adoption

December 15, 2008 1 comment

this blog talks about how to get more and more FOSS exposure in schools and organizations.

from A Quantum of FOSS:

I believe it is important for every parent and taxpayer to contact their school district’s superintendent and/or IT department and voice their frustration over the money spent on a fairly useless education tool like MS Office when entirely sufficient free replacements exist. Parents and taxpayers need to make it known that wasting public funds in this way is not appropriate and may very well impact their votes on future funding efforts like bonds and mill levies.

Read full post here.

freeswitch knocks asterisk’s block off

December 4, 2008 10 comments

Freeswitch is gaining popularity among asterisk community these days and looks quite promising, we also migrated our office PBX from asterisk to freeswitch few months back and never faced any issue till now. freeswitch is built from the scratch to address scalability and deadlocks issue within channels,  it’s modular architecture makes it developer friendly.

Freeswitch‘s SIP stack is much better than Asterisk’s sip implementation, Freeswitch uses Sofia sip stack which is 100% RFC compliant(IETF RFC3261 specification). Other than SIP freeswitch supports IAX2, Jingle and Woomera.

Another great thing about freeswitch is that it keeps all its configuration (users/dialplan etc, etc) in XML files. Another more interesting this is unlike asterisk’s dial patterns (e.g. _NXX) freeswitch uses PCRE regular expressions.

Freeswitch comes with an enterprise grade eventing engine, features software based conferences (no hardware timing source required), detailed cdr in XML(btw, i really loved the way freeswitch formats call flow in CDR, specially transfer calls).

Here is a list of Features and possible freeswitch uses:

Possible Uses

  • Rating & Routing Server
  • Transcoding B2BUA
  • IVR & Announcement Server
  • Conference Server
  • Voicemail Server
  • SBC (Session Border Controller)
  • Basic Topology Hiding Session Border Controller
  • Zaptel, Sangoma, Rhino, PIKA Hardware Support (Analog and PRI)

Features

  • Centralized User/Domain Directory (directory.xml)
  • Nano Second CDR granularity
  • Call recording (In Stereo caller/callee left/right)
  • High Performance Multi-Threaded Core engine
  • Configuration via CURL to your http server (xml_curl).
  • XML Config files for easy parsing.
  • Protocol Agnostic
  • Configurable RFC2833 Payload type
  • Inband DTMF generation and detection.
  • Software based Conference (no hardware requirement)
  • Wideband Conferencing
  • Media / No Media modes
  • Proper ENUM/ISN dialing built in
  • Detailed CDR in XML
  • Radius CDR
  • Subscription server
    • Shared Line Appearances
    • Bridged Line Appearances
  • Enterprise/Carrier grade Eventing Engine. (XML Events, Name Value Events, Multicast Events)
  • Loadable File formats and streaming
  • Stream to Shoutcast
  • Multi-lingual Speech Phrase Interface
  • ASR/TTS support (native and via MRCP)
  • Basic IP/PBX features
  • Automated Attendant
  • Custom Ring Back Tones
  • XML RPC support
  • Multiple format CDR’s supported
  • SQL Engine provides session persistence
  • Thread Isolation
  • Parallel Hunting
  • Serial Hunting
  • Mozilla Public License
  • Support
    • Paid support available
    • Free support via IRC & e-mail
  • Many supported codecs
    • G.722 (wideband)
    • G.711
    • G.726 (16k,24k,32k,48k) AAL2 and RFC3551
    • G.723.1 (passthru)
    • G.729 (passthru)
    • AMR (passthru)
    • iLBC
    • speex (narrow and wideband)
    • lpc10
    • DVI4 (ADPCM) 8khz and 16khz

break the firewall/isp — view blocked websites

December 2, 2008 9 comments

If a website is blocked by your ISP (or even government authorities). it is very likely that you can still gain access to those websites, this post will tell you how to bypass blockage by firewalls/ISPs, in order to achieve this goal we are going to use SSH tunneling to bypass firewalls and ISP’s rules/policies.

Preparation:

  1. windows users: download putty on your desktop.
    ubuntu users:
    no additional software/utility required.
  2. get an ssh account on a remote machine (e.g. an ssh server running at home), if you don’t have a machine running ssh service, you can still get ssh account from many paid and free ssh service providers listed here (a server in another country will help you browsing blocked websites by government agencies :)), I got a free account from rootshell.be and it’s tested.

Establishing the Tunnel:

for windows users I would recommend this video tutorial for tunnel set-up using putty.

Linux/Windows users can achieve this using following simple command.

ssh username@hostname -C -D 7070

where username is the username to connect with remote machine, hostname is ip or hostname of the remote machine, and 7070 is the tunnel port.

let me know if you liked this tip, comments and quries welcomed.

Categories: linux Tags: , , , ,