Whole document tree

Debian Euro HOWTO
Chapter 1 Introduction

1.1 Why euro support?

As of January 1st 2002, twelve European Union countries, and several others, are starting to use the euro as the only official currency. Thus, all the prices will be shown in euros and all the monetary transactions will use it. Euro is expected to become a common currency throughout Europe and even some other continents.

Computers, of course, need to correctly represent the euro in order for users to make their own documents (invoices, spreadsheets or whatever) using this currency, and read others' documents that use it. As the European Comission guidelines state, operating systems need to be ready to represent this character.

The euro is a currency but also the name of a symbol. Since the Unicode Standard 2.1 version (dated 1998) the EURO SIGN is added, so it's also an Unicode character that can be represented (interpreted) with different glyphs (different fonts can change height or width).

1.2 What is the euro symbol?

The euro symbol resembles the letter "e" -- it looks like a 'c' with two parallel horizontal lines that go through the middle of it. Some of the people will understand it better if we say it looks like the Quake symbol rotated 90 degrees clockwise :-)

The symbol is inspired by the Greek letter epsilon and also denotes the first letter of the word "Europe". The two parallel lines are meant to refer to the stability inside the euro area.

The official (ISO-compliant) abbreviature for the euro is EUR and can be used as representation for the currency.

1.3 Why all this fuss for just one character?

The problem is that changing the character involve a change in the font map used by the user. The font map is the list of character representations used by the system. Currently, most users in the euro-zone use the latin1 font map. The font map, however, is limited to 256 characters. The euro character is introduced by removing another character from the font map and calling this replacement a new font map. Latin9 (ISO-8859-15 or codepage 924 for IBM, usually shortened to latin0) replaces Latin1 (ISO-8859-1), and Latin10 (ISO-8859-16) replaces Latin2 (however Czech is not fully covered in Latin10 so it's not a full replacement, and it does cover Romanian which Latin2 didn't). Keep in mind that the font map is limited to 256 characters (see charsets(7))

Latin9 differs from Latin1 in eight positions: A4, A6, A8, B4, B8, BC, BD, BE where Euro, Scaron, scaron, Zcaron, zcaron, OEligature, oeligature and Ydiaeresis, are defined.

Of course, users already using UTF-8 fonts are not affected by this problem since unicode is a superset of all ISO 8859 sets plus the characters required to represent practically all known languages (see unicode(7)). However, Unicode support is currently far from complete. For more information read Unicode in X-Windows.

1.4 Standards

The euro definition is part of some ISO standards:

• The EUR currency code (numeric code 978) is a part of the ISO-4217 standard.

• For 8-bit systems, the ISO/IEC defines the new charset 8859-15 (also known as latin 9) and 8859-16 (also known as latin 10) where the euro symbol replaces the international currency symbol in the 164 position (hex A4)

• The Unicode system uses a 16 bit symbol, the euro has been assigned 8364 (hex 20AC) as part of ISO/IEC-10646-1

• The screen representation (font) for the euro is part of the ISO/IEC-10036 standard. The glyph is the real representation (bit pattern) of the character. The euro is assigned the 8059 glyph.

• The World Wide Web Consortium uses € as the representation for the symbol in HTML 4.0 (See http://www.w3.org/TR/html4/sgml/entities.html#h-24.4.1)

The European Comission has published in its official recommendations both short term and long term fixes for the euro character. The short term solution is fixed by having keyboards input the euro character through the AltGr+E combination (AltGr is the 'Alt' key to the right of the spacebar), the long term solution considers using a new key for the euro character. Most keyboard manufacturers have only implemented the short-term solution by including a euro representation under the 'E' key. The operating system must take this input and convert it into the euro symbol internally. However:

• The international US keyboard and the greek latin use AltGr+5 and Ctrl+Alt+5 for euro representation.

• The greek keyboard uses AltGr+? for euro representation.

• The english and irish keyboards use the combinations AltGr+4 and Ctrl+Alt+4

• The hungarian and polish keyboards use the AltGr+U combination.

In this document, however, most examples will assume that the euro symbol will be generated by typing AltGr+E (the euro-test program assumes this too).

1.5 Is Debian euro-ready?

The Debian operating system can be properly configured to show the euro character, both in console and in the X windowing system since the 2000 release Debian 2.2 (aka 'potato'). However, many users have not properly configured that support since then, and there are some caveats in configuration that have not been completely fixed until Debian woody (future 3.0).

In any case, some problems might arise from programs defaulting to ISO-8859-1 or even ASCII-US, and some even can't be configured properly to use ISO-8859-15 (bug reports through the Bug Tracking System should/will be filed against them).