From: Rainer <wolf.rainer@...>
Date: 2007-11-04T19:45:16+09:00
Subject: Re: The return of the son of Umlaute

On 1 Nov., 16:24, ed.oda...@wonado.de wrote:
> Take a look tohttp://www.gnu.org/software/libiconv/
>
> I found there everything that is necessary to do the job :-)
>
> C:\Dokumente und Einstellungen\wolfgang>irb
> irb(main):001:0> require 'iconv'
> => true
> irb(main):002:0> Iconv.iconv('utf-8', 'CP850', "äöü")
> => ["\303\244\303\266\303\274"]
> irb(main):003:0> Iconv.iconv('ISO-8859-1', 'CP850', "äöü")
> => ["\344\366\374"]
>
> Wolfgang Nádasi-Donner
> --
> Posted viahttp://www.ruby-forum.com/.

Hello Wolfgang,

thank you very much, the second line above did the trick, and it works
both ways! The irony is that I actually had seen the libiconv page you
referred me to. What I had failed to see was the fact that the long
lists of character encodings and their explanations were meant to be
THE ACTUAL STRINGS you had to replace for "to" and "from" in the iconv
method. Argh!

Thanks also to mortee and 7stud and to everyone who helped me on this.
This newsgroup has been a wonderful experience so far.

As a little "Thank you" to this group, I'm giving a short summary for
anyone who gets stuck in the same place as me, written with a
"cookbook approach" (sort of):

PROBLEM: When you read text files and use their contents in irb, some
of the characters look strange.

REASON: The character encoding you are using for your text files is
different from the one in your irb shell.

SOLUTION:

1. Find out which character encoding is used in your irb shell.

The solution for step 1 depends on your operating system. If you're
working with Windows, open "cmd.exe" and type "chcp" at the prompt. If
you're in Germany like me, you'll probably read this:

> Aktive Codepage: 850.

2. Find out about the character encoding for your files.

I didn't use a command line tool for this. In my case it's ISO-8859-1
(Western European countries). You will find a good introduction here:
http://en.wikipedia.org/wiki/ISO_8859 (and here if you're German:
http://de.wikipedia.org/wiki/ISO_8859).

3. Find the function to convert between the encodings.

The function is

	Iconv.iconv(to, from, *strs)

from the iconv standard library. An explanation for the character
encodings used by iconv is here: http://www.gnu.org/software/libiconv/

4. Find out what to replace for "to" and "from".

This was the hard part for me. I failed to see that the explanations
on the libiconv page are the actual strings you have to replace. Small
excerpt:

----from libiconv page----
It provides support for the encodings:

European languages
ASCII, ISO-8859-{1,2,3,4,5,7,9,10,13,14,15,16}, KOI8-R, KOI8-U, KOI8-
RU, CP{1250,1251,1252,1253,1254,1257}, CP{850,866},
Mac{Roman,CentralEurope,Iceland,Croatian,Romania},
Mac{Cyrillic,Ukraine,Greek,Turkish}, Macintosh
...
----from libiconv page----

This means (of course): 'ISO-8859-1' or 'ISO-8859-2' or 'CP850' or
'CP866' and so on.

5. The actual code for converting the strings back and forth on my
Windows XP machine:

require 'iconv'
my_string = 'Motörhead'

#Converting from the shell to a file
shell_to_file = Iconv.iconv('ISO-8859-1', 'CP850', my_string)
f = File.open("umlaut.txt", "w")
f << shell_to_file
f.close

#Converting strings from the file in order to read it in the shell
f = File.open("umlaut.txt", "r")
string_from_file = f.readlines.first
file_to_shell = Iconv.iconv('CP850', 'ISO-8859-1', string_from_file)

That's it!

What I'm trying to do here is putting Martin Fowlers tip "if I want to
learn about something I write about it." to good use, so: Any comments
and criticism to this solution are appreciated.

Cheers,

Rainer