The value types recognized are string,
localestring,
boolean, and
numeric.
Values of type string may contain all ASCII
characters except for control characters.
Values of type localestring are user displayable,
and are encoded in UTF-8.
Values of type boolean must either be the string
true or false.
Values of type numeric must be a valid floating
point number as recognized by the %f specifier for
scanf in the C locale.
The escape sequences \s, \n,
\t, \r, and
\\ are supported for values of type
string and localestring, meaning
ASCII space, newline, tab, carriage return, and backslash, respectively.
Some keys can have multiple values. In such a case, the value of the key
is specified as a plural: for example, string(s). The
multiple values should be separated by a semicolon, and the value of the
key should have a semicolon as trailing character. Semicolons in these
values need to be escaped using \;.