Vietnamese input method (VNIM)

The Vienamese input method (VNIM) is similar to the single-byte input method (SIM), except that it is customized for processing the Vietnamese language.

Specifically, it is designed to prevent entry of combinations of Vietnamese characters (tone marks), that are not valid in the Vietnamese language. The Vietnamese tone-mark characters can only be entered immediately after one of the Vietnamese vowels (a, e, i, o, u, y, a-circumflex, e-circumflex, o-circumflex, a-breve, o-horn, or u-horn).

The VNIM supports a single keyboard layer, including some pre-composed characters and Vietnamese tone marks.

The VNIM supports the IBM-1129 code set.