add: new->command_line_arg = command_line_arg;
context: queue_directory (const char *name, const char *realname){  struct pending *new;  new = XMALLOC (struct pending, 1);  new->realname = realname ? xstrdup (realname) : NULL;  new->name = name ? xstrdup (name) : NULL;  new->next = pending_dirs;  pending_dirs = new;}