bpf_dynptr_from_file
BTF_ID_FLAGS(func, bpf_dynptr_from_file)
BTF_ID(func, bpf_dynptr_from_file)
if (bpf_dynptr_from_file(file, 0, &dynptr))
if (bpf_dynptr_from_file(file, 0, &dynptr))
err = bpf_dynptr_from_file(file, 0, &dynptr);