Paolo Donadeo — LifeLOG/Digital life

Online backup with Crashplan: my experience

p.donadeo@gmail.com (Paolo Donadeo) — Sun, 25 Mar 2012 13:06:02 +0000

Following this article of Lifehacker I decided to give a try to Crashplan, an online "cloud" backup service that seemed very promising to me because it supports many platforms (Linux and Android included) and offers an unlimited space plan for one computer for only $36 a year.

Installing the client for Linux is very easy, and presents all the typical backup options (timing, include/exclude paths, and so on).

I decided to include all the directory I already backup with a script of mine on a USB external hard drive.

The problem here is visible in the screenshot I saved: the estimated time for completing the first backup was 52 days!

It's not Crashplan fault, of course, but the fact is that here in Italy we are still very far from using a remote service like that.

Maybe I'll retry again in a a few… years.

Thanks Mr. Ritchie

p.donadeo@gmail.com (Paolo Donadeo) — Thu, 13 Oct 2011 21:46:52 +0000

Today Unix, or some other operating system deeply inspired by Unix, is pervasive: servers, embedded devices (notably Android, but it's only one) and the “revolutionary” Mac OSX is itself an incarnation of the ideas and works of Dennis Ritchie.

Dennis Ritchie worked on Unix more than 40 years ago, and my questions is: what will we use in forty years? Probably something Dennis Ritchie was working some months ago.

Thanks Mr. Ritchie.

Google+ and your privacy

p.donadeo@gmail.com (Paolo Donadeo) — Thu, 07 Jul 2011 22:02:02 +0000

Yesterday I was impressed by a privacy warning of Google+. While I was resharing a friend's post, Google+ remembered me that the original post had a limited visibility, and to take account of this fact. Click the image on the left to read the original message.

So Google+ starts it's journey with a strong accent to your privacy concern: you are invited not to tell everyone your business, because it's a valuable information, only Google wants to know... ;-)

Buon compleanno… da Google

p.donadeo@gmail.com (Paolo Donadeo) — Fri, 27 May 2011 21:05:14 +0000

Oggi è il mio compleanno, e questa non è più una novità da molti anni ormai. La prima persona che oggi mi ha fatto gli auguri di buon compleanno è stata la mia amica Valeria, a mezzanotte e cinque.

La seconda “entità” a farmeli è stato… Google! La prima ricerca che ho fatto, questa mattina, mostrava un logo di Google con un pacco regalo ed una torta. Come al solito, quando appare un logo custom, vado col mouse sul logo per scoprire di cosa si tratta.

Sotto il cursore è apparsa la scritta “Happy Birthday Paolo!”. Non ci potevo credere e, per chi in effetti non ci credesse, invito a cliccare sull'immagine in alto.

La prima considerazione è stata: ma che simpatici! La seconda non è stata una considerazione, ma una sensazione : un brivido lungo la schiena. Certo è tutto ovvio, non ci vuole chissà quale analisi o data mining per scoprire qual è la data del mio compleanno, visto che nel mio profilo di Google ce l'ho messa, anche se privata, nel senso che non ne ho autorizzato la pubblicazione.

Il problema qui non è infatti se altri possano scoprire informazioni personali, ma di quante informazioni aggregate disponga un'unica azienda. Cosa deve accadere perché iniziamo a preoccuparci?

Afterthought (about Unity)

p.donadeo@gmail.com (Paolo Donadeo) — Wed, 11 May 2011 23:18:00 +0000

In my previous post I expressed a strong opinion about Unity, the new graphic shell included in the latest release of Ubuntu, branding it as unusable.

Actually, I was wrong. My bad feeling was due to the novelty of ideas developed in Unity, and my the superficiality in testing it.

I don't know how Gnome Shell 3 compares with Unity, simply because I didn't tested the new Gnome Shell yet, but for sure Unity is a good project and represents a very interesting approach.

Unity

p.donadeo@gmail.com (Paolo Donadeo) — Sat, 30 Apr 2011 15:05:00 +0000

My checklist for today:

try the new Ubuntu shell, Unity: done. Verdict: unusable.
try Gnome Shell 3: done. Verdict: unstable.

This time I pass, let's see the next Ubuntu release if it will be more stable and usable.

Strange messages

p.donadeo@gmail.com (Paolo Donadeo) — Fri, 04 Feb 2011 22:40:00 +0000

I just learned that, if your DVD burner or the medium you just inserted into it cannot run at 16x speed, it's safe to burn at 17x.

You never stop learning!

Installing OCaml Batteries

p.donadeo@gmail.com (Paolo Donadeo) — Mon, 13 Dec 2010 22:55:00 +0000

In this post I want to help OCaml newcomers to install Batteries. The task is trivial under Linux, while it's a bit tricky under Windows, because OCaml still lacks a self-contained Windows installer.

My assumption is that the reader is a coder, so I will not explain everything… Let's start with the easy part: Linux.

Linux

The installation of OCaml + Batteries under a Debian/Ubuntu system couldn't be easier, thanks the the hard work of the Debian OCaml Task Force. So open a terminal and type:

$ sudo aptitude install ocaml-batteries-included

That's all for Debian/Ubuntu. I don't know how Fedora works, but I think it's easy to install Batteries using YUM, something like:

$ yum install ocaml-batteries-included

If a RPM package for Batteries wasn't available, you could still install OCaml, Camomile (the Unicode library), and compile Batteries from sources, as described below for the Windows OS.

Windows

As said, this OS still lacks a self contained installer which is in progress, at least for installing OCaml. Since many OCaml versions are available for Windows, with different pros and cons, I had to decide which one to use, and I decided to follow the simplest path to reach the goal of installing all the stuff we need. The Cygwin port is by far the simplest way.

Download Cygwin setup and double click the executable. In Windows Vista/7 (I made my test on a Windows 7 64bit box) you will be required to allow the program to be run a couple of times, as usual ;-) …
when the list of available packages appears, select: each and every package containing "caml" (see the screenshot below), and also make, m4, libncurses-devel, git, wget and rlwrap;
open the Cygwin shell;

download the Findlib library, version 1.2.6:

$ wget https://download.camlcity.org/download/findlib-1.2.6.tar.gz

unpack, compile and install Findlib:

$ tar -xpzf findlib-1.2.6.tar.gz
$ cd findlib-1.2.6/
$ ./configure
$ make
$ make install

download, unpack, compile and install Camomile 0.8.1:

$ wget https://prdownloads.sourceforge.net/camomile/camomile-0.8.1.tar.bz2
$ tar -xpjf camomile-0.8.1.tar.bz2
$ cd camomile-0.8.1/
$ ./configure
$ make
$ make install

the last step is to download compile and install Batteries itself. I wasn't able to compile the latest stable release (1.2.2), for an obscure preprocessor error, but using the latest GIT branch everything went smoothly. So here are the steps:
```
$ git clone git://github.com/ocaml-batteries-team/batteries-included.git
$ cd batteries-included/
$ make camomile82
$ make all doc
$ make install install-doc
```

Testing the installation

Before starting to play with the library and the toplevel (the OCaml REPL is called toplevel) let's put into action a couple of helpers.

The OCaml toplevel doesn't support readline. To get this feature back we add an alias to .bashrc. This works in both Linux and Windows:
```
alias ocaml='rlwrap -H /home/paolo/.ocaml_history -D 2 -i -s 10000 ocaml'
```
restart the terminal or load another bash;

we need to load Batteries in the toplevel. This is not strictly necessary, but it helps a lot and the Batteries ASCII logo is wonderful :-). All we need is to create a file named .ocamlinit in the home directory. Open your favorite editor and put this phrases in ~/.ocamlinit:

let interactive = !Sys.interactive;;
Sys.interactive := false;; (*Pretend to be in non-interactive mode*)
#use "topfind";;
Sys.interactive := interactive;; (*Return to regular interactive mode*)

Toploop.use_silently 
             Format.err_formatter (Filename.concat (Findlib.package_directory 
             "batteries") "battop.ml");;

If everything went well you can now type ocaml and something like this should appear:

$ ocaml
        Objective Caml version 3.11.2

      _________________________
    [| +   | |   Batteries   - |
     |_____|_|_________________|
      _________________________
     | -  Type '#help;;' | | + |]
     |___________________|_|___|


Loading syntax extensions...
	Camlp4 Parsing version 3.11.2

Conclusions

This (rather boring) post has been devoted to the installation details of Batteries under Windows, where it presents some difficulties for newbies. Next time we will start on exploring the library with simple examples to exploit its strength.

Pearls of OCaml Batteries (1)

p.donadeo@gmail.com (Paolo Donadeo) — Sun, 05 Dec 2010 15:15:00 +0000

OCaml is known to be a powerful functional programming language, but one of its presumed weakness is a relatively poor standard library.

By accident, I'm one of the few people on the planet considering this very clean and virtually bug free library a feature and not a bug, but this is only an opinion.

The standard library contains everything you need to build applications and other libraries, but it's essential, forget something like the Python standard library and things like “sending an email in one line of code”. Instead, think of the C standard library (plus some important data structures missing in the libc).

More than two years ago the OCaml community decided to start the development of a library containing all the conveniences that are missing in the standard library. The project is OCaml Batteries Included and I'd like to introduce the reader with a series of posts, aimed to cast a light on various aspects of the library, without pretending to be an exhaustive tutorial.

The posts will be targeted at novice OCaml programmers because I think that an experienced OCaml hacker already uses "Batteries" or, in any case, he understand the library API and doesn't need help from this blog.

Before starting with the (boring) installation details, I want to give you a taste of Batteries, to show how a simple task could be written in a more natural way using Batteries modules, in comparison with a vanilla implementation. Let's take this simple task: we want to read a file by lines and print on the terminal only those lines containing a particular substring.

A simple and actually working solution is proposed by the PLEAC-Objective CAML project, it's the very first example of the file access section. Here is the proposed code:

let () =
  let in_channel = open_in "/usr/local/widgets/data" in
  try
    while true do
      let line = input_line in_channel in
      try
        ignore (Str.search_forward (Str.regexp_string "blue") line 0);
        print_endline line
      with Not_found -> ()
    done
  with End_of_file ->
    close_in in_channel

Now let's rephrase using Batteries:

Enum.iter
  (fun l ->
    if BatString.exists l "blue"
    then print_endline l)
  (open_in "/usr/local/widgets/data" |> BatIO.lines_of)

The result is the same, but the code is much cleaner and far more idiomatic for a functional language.

Next time we will see how to install OCaml and Batteries, under Linux of course, but hopefully even under Windows.

Lyrics in Banshee

p.donadeo@gmail.com (Paolo Donadeo) — Thu, 02 Dec 2010 23:16:00 +0000

Is it only me, or the lyrics plugin of Banshee (1.8.0) doesn't work at all?

How is it possible not to find the lyrics of “Gimme Some Lovin'” of the Blues Brothers?