National Language Support Guide and Reference

Simplified Chinese Input Method (ZIM-UCS)

The UCS-2 code set consists of almost all character groups. The following character groups exist for the ZH_CN locale:

• ASCII (English)
• Glyphs
• Chinese, Japanese, and Korean (CJK) Characters (unification characters)

The CJK character set contains 20,992 character positions, but only 20,902 positions are assigned to Chinese characters.

The pronunciation of simplified Chinese is represented by phonetic symbols called Bopomofo. There are 25 phonetic symbols. Simplified Chinese characters are represented by one to three phonetic symbols.

ZIM-UCS features the following characteristics:

• The following commonly used input methods exist:

  Intelligent ABC

  An input method based on the phonetic representation of Chinese characters.

  Pin Yin Input Method

  An input method based on the phonetic representation of Chinese characters. A Chinese character is divided into one or several phonemes according to its pronunciation.

  Wu Bi (Five Strike) Input Method

  An input method based on the grapheme representation of Chinese characters. According to the WuBi grapheme input method, Chinese characters are classified into three levels: stroke, radical and single-character.

  Zheng Ma

  An input method based on the grapheme representation of Chinese word.

  Biao Xing Ma Input Method

  An input method in which a Chinese character is divided into several components,or radicals. When coding a character, these radicals are presented with the corresponding English letters.

  Internal Code Input Method

  An input method in accordance with the code table defined in GB18030 (Chinese Internal Code Specification) and UCS-2 (Unicode System Version 2).

• Half-width and full-width character input. Supports ASCII characters in both single-byte and multibyte modes.
• Auxiliary window to support all the candidate lists. For example, Intelligent ABC generate a list of possible characters that contain the same sound symbols (radicals). Users select the desired characters by pressing the conversion key.
• Over-the-spot pre-editing drawing area. Allows entry of radicals in reverse video area that temporarily covers the text line. The complete character is sent to the editor by pressing the conversion key.

The UCS-ZIM files are in the /usr/lib/nls/loc directory.

The UCS-ZIM keymap is in the /usr/lib/nls/loc/ZH_CN.UTF-8.imkeymap directory.

Chinese (CJK) Character Processing

UCS-ZIM is invoked by pressing one of the input method keys. Each radical or phonetic symbol is assigned to a key. The user inputs radicals or phonetic symbols to an over-the-spot pre-editing area. For internal code input method, a character is generated when the last key is pressed. Other input methods generate a list of candidates that display in a window. The user chooses the desired character by selecting the candidate number. Invalid input generates a beep and an error message. The glyphs can be input using the ABC input method.