编程实践char *指向const的指针或指向const的数组

Question

I know that following is bad programming practice

char * p1 = "myBad"  ;  

The above is bad as const "myBad" memory is getting pointed by non Const pointer . Compilers allow p1 as to support backward compatibility with C

IS the following a bad practice too ?

char p2[]="myBadORGood";

Whats the difference betweeen p1 and p2 . DOes compiler make a non-const copy for p2 ? I think i read somewhere that p2 is fine but not sure ..

Answer 1

p2由字符串文字初始化，即它是字符串文字的副本 ，因此p2为非const可以：

char p2[]="myGood";

Answer 2

The first is not only bad practice but deprecated in C++ (C++03; according to chris' comment this is even illegal now in C++11 ).

The second is totally fine, the string literal is only used as a (read-only) "model" to initialize a new, independent array. Thus, the short

char arr[] = "abc";

is equivalent to the longer

char arr[] = { 'a', 'b', 'c', '\0' };

and can even be written like this:

char arr[4];
arr[0] = 'a';
arr[1] = 'b';
arr[2] = 'c';
arr[3] = '\0';

(but don't write code like that! ^^)