Function update

builtin/remote.c:1701–1739

}

static int update(int argc, const char **argv, const char *prefix,
		  struct repository *repo UNUSED)
{
	int i, prune = -1;
	struct option options[] = {
		OPT_BOOL('p', "prune", &prune,
			 N_("prune remotes after fetching")),
		OPT_END()
	};
	struct child_process cmd = CHILD_PROCESS_INIT;
	int default_defined = 0;

	argc = parse_options(argc, argv, prefix, options,
			     builtin_remote_update_usage,
			     PARSE_OPT_KEEP_ARGV0);

	strvec_push(&cmd.args, "fetch");

	if (prune != -1)
		strvec_push(&cmd.args, prune ? "--prune" : "--no-prune");
	if (verbose)
		strvec_push(&cmd.args, "-v");
	strvec_push(&cmd.args, "--multiple");
	if (argc < 2)
		strvec_push(&cmd.args, "default");
	for (i = 1; i < argc; i++)
		strvec_push(&cmd.args, argv[i]);

	if (strcmp(cmd.args.v[cmd.args.nr-1], "default") == 0) {
		repo_config(the_repository, get_remote_default, &default_defined);
		if (!default_defined) {
			strvec_pop(&cmd.args);
			strvec_push(&cmd.args, "--all");
		}
	}

	cmd.git_cmd = 1;
	return run_command(&cmd);
}

static int remove_all_fetch_refspecs(const char *key)
{