Attach an input
#include <mm/renderer.h>
int mmr_input_attach(mmr_context_t *ctxt, const char *url, const char *type)
Attach an input track or playlist. If the context already has an input, mm-renderer detaches it first.
The input type affects how mm-renderer responds to certain playback requests. For instance, when jumping to new track positions with mmr_seek(), the way that you specify the new position depends on the input type. Also, mmr_list_change() applies to playlist only.
Zero on success, -1 on failure (use mmr_error_info())