strcpy doesnot work

[t im]

Just check the code below:

char* s1 = "hello";
char* s2 = "world";
cout<<s2<<endl; // world
strcpy(s2, s1);
cout<<s2<<endl; // world 

Why does s2 remain the same after strcpy?
Thanks in advance.

[Peter87]

s2 points to read-only memory.

You should actually be using const (modern compilers will at least warn if you don't).

const char* s1 = "hello";
const char* s2 = "world";

If you did this you would have got a compilation error telling you that you're not allowed to pass a pointer to const as the first argument to strcpy.

What you probably want is:

char s2[] = "world";

or

char s2[6];

Just make sure it's big enough to hold the string that you're going to store in it (including the null terminator).

[Peter87]

In case you're not aware, there is a string class type in the standard library (inside the <string> header) which makes this much easier (and less error prone).

std::string s1 = "hello";
std::string s2 = "world";
std::cout << s2 << "\n"; // world
s2 = s1;
std::cout << s2 << "\n"; // hello 

[t im]

Get it.
Thanks for your help.