Although I wouldn't really know for what you would like to use these
features, they are provided for ISO complicancy.
Define that term-input (see read_term/3)
maps each character read as
CharIn to the character CharOut. Character
conversion is only executed if the prolog-flag
is set to
true and not inside quoted atoms or strings. The initial
table maps each character onto itself. See also current_char_conversion/2.
Queries the current character conversion-table. See char_conversion/2