Do all prog/map/link objects have IDs?

[dthaler]

Libbpf has APIs like
bpf_prog_get_next_id, bpf_map_get_next_id, and bpf_link_get_next_id
to enumerate object IDs.

Question: are IDs
a) always generated for every object created, OR
b) only generated when stored as values in another object?

[dthaler]

Answer appears to be that all objects have IDs, so they can be enumerated with APIs like bpf_*_get_next_id, and thus with commands like "bpftool prog show" etc.