Re: [PATCH v3 net-next 4/4] bpftool: implement cgroup bpf operations

On 12/8/17 4:46 PM, Jakub Kicinski wrote:

quoted

+	argc -= 2;
+	argv = &argv[2];
+	prog_fd = prog_parse_fd(&argc, &argv);
+	if (prog_fd < 0)
+		goto exit_cgroup;
+
+	for (i = 0; i < argc; i++) {
+		if (strcmp(argv[i], "allow_multi") == 0) {
+			attach_flags |= BPF_F_ALLOW_MULTI;
+		} else if (strcmp(argv[i], "allow_override") == 0) {
+			attach_flags |= BPF_F_ALLOW_OVERRIDE;

I don't feel about this strongly but as I said I was trying to follow
iproute2's conventions, and it allows aliasing.  So if you type "ip a"
it will give you the first thing that starts with a, not necessarily
alphabetically, more likely in order of usefulness or order in which
things were added.  IOW if "allow_" selects "allow_mutli" that's what I
would actually expect it to do..

Maybe others disagree?

The iproute2 syntax is very user friendly, and I agree with following
the conventions.

With respect to the attach flags, allow_yyyyy is a lot to type, but
having 'a .. allow_' mean one flag over the other is going to be
confusing. Perhaps dropping the 'allow_' prefix in favor of just 'multi'
and 'override' and doing prefix match on it? User commands do not need
to follow flag names precisely.