🆕 cd命令

user/apps/shell/cmd_help.c

@@ -0,0 +1,23 @@
+#include "cmd_help.h"
+#include <libc/stdio.h>
+struct help_table_item_t
+{
+    void (*func)();
+};
+struct help_table_item_t help_table[] = {
+    {shell_help_cd},
+};
+
+static const int help_table_num = sizeof(help_table) / sizeof(struct help_table_item_t);
+
+void shell_help()
+{
+    printf("Help:\n");
+    for (int i = 0; i < help_table_num; ++i)
+        help_table[i].func();
+}
+
+void shell_help_cd()
+{
+    printf("Example of cd: cd [destination]\n");
+}