public int64 get_int64 (string group_name, string key) throws KeyFileError
Returns the value associated with
group_name as a signed 64-bit integer.
This is similar to get_integer but can return 64-bit results without truncation.
a non-null KeyFile
a non-null group name
a non-null key
the value associated with the key as a signed 64-bit integer, or 0 if the key was not found or could not be parsed.