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Chapter 1 Solaris Internationalization OverviewThis chapter introduces the new features and the key concepts of Solaris internationalization and localization. The chapter covers the following topics. About the Solaris Internationalization ArchitectureThe current Solaris release includes a number of new features, including Unicode 4.0 support for the UTF-8 locales, enhanced keyboard support, and several improvements to the mp print filter. The Solaris internationalization architecture eases the development, the deployment, and the management of applications and language services around the world. A single multilingual product provides support for 39 different languages and 162 locales. In addition, support is available for the complex text layout that is required for Thai and Hindi scripts. Bidirectional text capability is also supported for languages such as Arabic and Hebrew. Input methods, character sets, codeset conversion, and other language-related features are supported for a number of different Solaris locales. You can deploy applications in multiple language environments by following standard APIs. You can also customize language attributes, change converter tables, or add a new input method editor in the Solaris environment. The source code for the Solaris X globalization framework was released to the open source community in the fall of 2000. That release enables you to follow a common reference implementation to enhance the compatibility and the interoperability of global applications. The codeset independent approach to globalization enables you to operate in both native language and Unicode locales. The Solaris framework provides the power to scale across platforms. A rich set of data converters ensures interoperability between various encodings and different third-party platforms. The Solaris platform also enables multinational corporations to scale their server administration worldwide. Unlike competing platforms, the Solaris platform uses a service-based approach to administration of language services. Server administrators can enable language services remotely across a worldwide network, regardless of the client system. This client-independent approach enables system upgrades without changing client applications. For example, a user does not have to change a local client application in order to read email in Arabic sent from an Internet cafe in Paris. New Internationalization and Localization FeaturesThe following new features are available in the current Solaris release:
Internationalization and Localization OverviewInternationalization and localization are different procedures. Internationalization is the process of making software portable between languages or regions, while localization is the process of adapting software for specific languages or regions. Internationalized software can be developed using interfaces that modify program behavior at runtime in accordance with specific cultural requirements. Localization involves establishing online information to support a language or region, called a locale. Unlike software that must be completely rewritten before it can work with different native languages and customs, internationalized software does not require rewriting. The internationalized software can be ported from one locale to another without change. The Solaris system is internationalized, providing the infrastructure and interfaces you need to create internationalized software. Basic Steps in InternationalizationAn internationalized application's executable image is portable between languages and regions. To internationalize software:
Message strings are translated for a language or region. A locale includes the message strings and methods to specify sorting. To use a localized version of a product, the user sets certain environment variables. The product then displays messages that are translated into the language of the locale. Date, time, currency, and other information is formatted and displayed according to locale-specific conventions. Message translations and online help contents are provided throughout different layers, as illustrated in the following diagram. Figure 1–1 Functions and Structure of Locales in the Solaris Operating System
Localization Functions in Solaris InterfacesThe OS (operating system) locale layer provides the basic locale database and functions that are plugged into the OS system interface at the application's runtime. Applications access these OS locale modules through standard APIs. The X11 locale layer provides the interface to the X input method and X output method to X11 applications for local text input and display. Fonts enable applications to display characters from various languages. CDE/Motif is built on top of the X11 window system. Hence, CDE/Motif can utilize the X11 locale capability through X11 APIs. Solaris localizations have various locale-specific configurations for CDE applications in order to make the desktop functional within the target locale. Message translations and online help contents are provided throughout different layers. What Is a Locale?A key concept for application programs is that of a program's locale. The locale is an explicit model and definition of a native-language environment. The notion of a locale is explicitly defined and included in the library definitions of the ANSI C Language standard. A locale consists of a number of categories for which country-dependent formatting or other specifications exist. A program's locale defines its code sets, date and time formatting conventions, monetary conventions, decimal formatting conventions, and collation (sort) order. A locale can be composed of a base language, country (territory) of use, and an optional codeset. Codeset is usually assumed. For example, German is de, an abbreviation for Deutsch, while Swiss German is de_CH, CH being an abbreviation for Confederation Helvetica. This convention allows for specific differences by country, such as currency unit notation. More than one locale can be associated with a particular language, which allows for regional differences. For example, an English-speaking user in the United States can select the en_US locale (English for the United States), while an English-speaking user in Great Britain can select en_GB (English for Great Britain). Generally the locale name is specified by the LANG environment variable. Locale categories are subordinate to LANG but can be set separately, in which case they override LANG. If the LC_ALL operand is set, it overrides LANG and all the separate locale categories. The locale naming convention is: language[_territory][.codeset] [@modifier] where a two-letter language code is from ISO 639, a two-letter territory code is from ISO 3166, codeset is the name of the codeset that is being used in the locale, and modifier is the name of the characteristics that differentiate the locale from the locale without the modifier. All Solaris product locales preserve the Portable Character Set characters with US-ASCII code values. For more information on the portable character set, refer to “X/Open CAE Specification: System Interface Definitions, Issue 5” (ISBN 1–85912–186–1). A single locale can have more than one locale name. For example, POSIX is the same locale as C. C Locale – the Default LocaleThe C locale, also known as the POSIX locale, is the POSIX system default locale for all POSIX-compliant systems. The Solaris Operating System is a POSIX system. The Single UNIX Specification, Version 3, defines the C locale. Register to read and download the specification at: http://www.unix.org/version3/online.html. You can specify that your internationalized programs run in the C locale, in one of two ways:
To check the current locale settings in a terminal environment, run the locale(1) command. system% locale Full and Partial LocalesA full Solaris locale has all of the listed functions and the localized system messages in the relevant language. Partial locales have no localized messages installed. All locales in the Solaris environment are capable of displaying localized messages, provided that localized messages for the relevant language are installed. For example, the following locales can be either partial or full locales:
When the German message translations are installed from the Languages CD, all of the above locales become full locales because they have access to a fully translated desktop. The Languages CD contains message translations for the following languages and locales:
All partial locales are available on the Software CD. Message translations are available on the Languages CD. All English locales are also full locales and are available on the Software CD. Behavior Affected by LocalesDifferent cultures often use different conventions to format numbers, to write the date and time, to delimit words and phrases, or to quote written and spoken material. A locale determines how the following operations, files, formats, and expressions are handled for different regions:
The Solaris environment separates language and culture-dependent information from the application and saves the information outside the application. This method eliminates the need to translate, rewrite, or recompile the application for each market. The only requirement to enter a new market is to localize the external information to the local language and customs. Locale CategoriesThe locale categories are as follows:
Using Locale Categories for LocalizationThe localization of a product should be done in consultation with native users in that target language or region. Certain information styles and formats might seem perfectly obvious and universal to the developer. However, to the user these formats could look awkward, wrong, or even offensive. The following sections describe the elements in the Solaris Operating System that you can customize to meet the localization requirements for your product. Time FormatsThe following table shows some of the ways in which different locales write 11:59 P.M. Table 1–2 International Time Formats
Time is represented by both a 12-hour clock and a 24-hour clock. The hour and minute separator can be either a colon ( : ) or a period ( . ). Time zone splits occur between and within countries. Although a time zone can be described in terms of how many hours it is ahead of, or behind, Coordinated Universal Time, UTC (or Greenwich Mean Time, GMT), this number is not always an integer. For example, Newfoundland is in a time zone that is half an hour different from the adjacent time zone. Daylight Savings Time (DST) starts and ends on dates that can vary from country to country. Many countries do not implement DST at all. Additionally, Daylight Savings Time can vary within a time zone. In the U.S. for example, the implementation is a state decision. Date FormatsThe following table shows some of the date formats used around the world. Variations can exist even within a country. Table 1–3 International Date Formats
Number FormatsGreat Britain and the United States are two of the few places in the world that use a period to indicate the decimal place. Many other countries use a comma instead. The decimal separator is also called the radix character. Likewise, while Great Britain and the United States use a comma to separate groups of thousands, many other countries use a period instead, and some countries separate thousands groups with a thin space. Data files containing locale-specific formats are frequently misinterpreted when transferred to a system in a different locale. For example, a file containing numbers in a French format is not useful to a British-specific program. The following table shows some commonly used numeric formats. Table 1–4 International Numeric Conventions
Note – No particular locale conventions exist that specify how to separate numbers in a list. International Monetary FormatsCurrency units and presentation order vary greatly around the world. Local and international symbols for currency can differ. The following table shows monetary formats in some countries. Table 1–5 International Monetary Conventions
The current release supports the Euro currency. Local currency symbols are still available for backward compatibility. Table 1–6 User Locales That Support the Euro Currency
Euro locales are based on the ISO8859–15 code set. Keep in mind that a converted currency amount can
require a different amount of space than the original amount, for example,
$1,000 can become The current status of the locale settings for locales within the euro zone is illustrated for the LC_MONETARY operand of the locale utility. The status for Germany, for example, is shown in the following table. Table 1–7 German Locale and Corresponding LC_MONETARY Operand
Language Word and Letter DifferencesThis section describes important differences between languages. Word DelimitersIn English, words are usually separated by a space character. Languages such as Chinese, Japanese, and Thai, however, often have no delimiter between words. Sort OrderSorting order for particular characters is not the same in all languages. For example, the character “ö” sorts with the ordinary “o” in Germany, but sorts separately in Sweden, where it is the last letter of the alphabet. In some languages, characters have weight to determine the priority of the character sequences. For example, the Thai dictionary defines sorting through the sequences of characters that have different weights. Character SetsCharacter sets can differ in the number of alphabetic characters and special characters. While the English alphabet contains only 26 characters, some languages contain many more characters. Japanese, for example, can contain over 20,000 characters and Chinese can contain an even higher number of characters. Western European AlphabetsThe alphabets of most western European countries are similar to the standard 26-character alphabet used in English-speaking countries. These alphabets often also include some additional basic characters, some marked or accented characters, and some ligatures. Japanese TextJapanese text is composed of three different scripts mixed together: Although each character in Hiragana has an equivalent in Katakana, Hiragana is the most common script, with cursive rather than block-like letter forms. Kanji characters are used to write root words. Katakana is mostly used to represent “foreign” words, that is, words imported from languages other than Japanese. Kanji has tens of thousands of characters, but the number commonly used has declined steadily over the years. Now only about 3500 are frequently used, although the average Japanese writer has a vocabulary of about 2000 Kanji characters. Nonetheless, computer systems must support more than 7000 characters in accordance with the Japan Industry Standard (JIS) requirements. In addition, there are about 170 Hiragana and Katakana characters. On average, 55% of Japanese text is Hiragana, 35% Kanji, and 10% Katakana. Arabic numerals and Roman letters are also present in Japanese text. Although completely avoiding the use of Kanji is possible, most Japanese readers find a text that is composed without any Kanji hard to understand. Korean TextKorean text can be written using a phonetic writing system called Hangul. Hangul has more than 11,000 characters, which consist of consonants and vowels known as jamos. About 3000 characters from the entire Hangul vocabulary of characters are usually used in Korean computer systems. Korean also uses ideographs based on the set invented in China, called Hanja. Korean text requires over 6000 Hanja characters. Hanja is used mostly to avoid confusion when Hangul would be ambiguous. Hangul characters are formed by combining consonants and vowels. After these characters are combined, they can compose one syllable, which is a Hangul character. Hangul characters are often arranged in a square, so that the group takes up the same space as a Hanja character. Arabic numerals, Roman letters, and special symbol characters are also present in Korean text. Thai TextA Thai character can be defined as a column position on a display screen with four display cells. Each column position can have up to three characters. The composition of a display cell is based on the Thai character's classification. Some Thai characters can be composed with another character's classification. If both characters can be composed together, both characters are in the same cell. Otherwise, they are in separate cells. Chinese TextChinese usually consists entirely of characters from the ideographic script called Hanzi.
If a character is not a root character, it usually consists of two or more parts, two being most common. In two-part characters, one part generally represents meaning, and the other represents pronunciation. Occasionally both parts represent meaning. The radical is the most important element, and characters are traditionally arranged by radical, of which there are several hundred. A single sound can be represented by many different characters, which are not interchangeable in usage. A single character can have different sounds. Some characters are more appropriate than others in a given context. The appropriate character is distinguished phonetically by the use of tones. By contrast, spoken Japanese and Korean lack tones. Several phonetic systems represent Chinese. In the People's Republic of China the most common is pinyin, which uses Roman characters and is widely employed in the West for place names such as Beijing. The Wade-Giles system is an older phonetic system, formerly used for place names such as Peking. In Taiwan zhuyin (or bopomofo), a phonetic alphabet with unique letter forms, is often used instead. Hebrew TextHebrew text is used for writing scripts in the Hebrew and Yiddish languages. Hebrew uses a bidirectional script. Hebrew letters are written and read from right to left, while numbers are read from left to right. Any English text that is embedded in Hebrew text is also read from left to right. Hebrew uses a 27-character alphabet, and takes punctuation marks and numbers from the standard Latin (or English) alphabet. Hebrew text also includes vowel and pronunciation marks. These marks appear either as a dot (dagesh) inside the base character, vowel marks below the character, or accents to the upper left of the character. These marks are generally only used in liturgical text, and are rarely seen in day-to-day use. Hebrew has no uppercase letters. Hindi TextHindi text is written in a script called Devanagari, which means the writing of the gods. Hindi is a phonetic language, and is written as a series of syllables. Each syllable is built up of alphabetic pieces (the Devanagari characters) of three types: consonant letters, independent vowels, and dependent vowel signs. The syllable itself consists of a consonant and vowel core, with an optional preceding consonant. Unlike English, which starts from a baseline, Devanagari characters hang from a horizontal line (called the head stroke) written at the top of the characters. These characters can combine or change shape depending on their context. Like Hebrew, Hindi text makes no distinction between uppercase and lowercase letters. Keyboard DifferencesNot all characters on the U.S. keyboard appear on other keyboards. Similarly, other keyboards often contain many characters not visible on the U.S. keyboard. Any keyboard can be used to input characters from any locale because input is handled by the Solaris Operating System. Note – On SPARC® machines, the Compose key can be used to produce any Latin character with a diacritic in any of the supported ISO8859 character sets. The Compose key can be used with Latin-based locales, but not with Korean, Chinese, or Japanese locales, except the UTF-8 locales. Differences in Paper SizesWithin each country, a small number of paper sizes are commonly used. Normally, one of those sizes is much more common than the others. Most countries follow ISO Standard 216: “Writing paper and certain classes of printed matter-Trimmed sizes-A and B series.” Internationalized applications should not make assumptions about the page sizes available to them. The Solaris system provides no support for tracking output page size. This tracking is the responsibility of the application program. The following table shows common international page sizes. Table 1–8 Common International Page Sizes
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