SCIM is a Smart Common Input Method platform which provides a
user-friendly and full-featured input method user interface for
POSIX-style operating systems.
Currently the SCIM project has a wide range of input methods
(some may need other libraries) covering more than 30 languages,
including (Simplified/Traditional) Chinese, Japanese, Korean,
and many European languages. Composing/Dead key support is
also one of the built-in features. In addition, several projects
have been established to design IMEngines for SCIM, and others
supply their own SCIM plugins.
To use scim, you need set something in ~/.xinitrc like:
export GTK_IM_MODULE="xim"
export XMODIFIERS="@im=SCIM"
then start scim:
scim -d 1> /dev/null 2> /dev/null
This is just a platform; you also need a special input method.
I used scim-fcitx for Chinese PinYin input.
I also will submit scim-fcitx to SlackBuilds.org later.