Specifies an unused argument (required by ANSI C).
Specifies the variable length argument list.
function allocates memory and copies its arguments into
a single list pointer,
which may be used as a value for arguments requiring a list value.
Any entries are copied as specified.
Data passed by reference is not copied;
the caller must ensure data remains valid for the lifetime
of the nested list.
The list should be freed using
when it is no longer needed.