lib3ds only provides access to the data within
.3ds files, along with some utility functions. It does not appear to have any kind of built-in playback functionality. You will need to build that yourself, but to do so you will need to access the data that lib3ds has loaded up.
Lib3dsTrack objects for various nodes in the file which define keyframe tracks for various attributes of the node.
You are probably interested in the tracks of
Lib3dsMeshInstanceNode, which are:
These tracks define keyframes for position, rotation, scale, and visibility of the mesh. The keyframes are of type
Lib3dsKey and contain value information as well as flags indicating which type of value information to use for that key (not all keys have sane values in all value fields).
There are various utility functions (in the
track_eval_* family) that allow you to evaluate the value of some specified track at some specified time t, which can help you in processing the data in the tracks so you don't have to do it all yourself.