Confusion on const char*

Question

Hi

We can have const int* and int* const.. I am aware about these two along with int const * as well as const int * const.

I have just captured these into sample code below:

Question is related to const char*

It is neither as per const int* or int* const

Am I missing something or const char* is totally different? What is constant in this declaration?
https://code.sololearn.com/c9ig21YSVy5e/?ref=app

Answer 1

Well

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const int* p1 = &a;
++a;//works as a is not const

p1 = &b;//works as pointer is not const

++p1;// works and p1 is not pointing to b now but points to some next memory location

//++(*p1);//not work as const int means int value is const and p1 cant modify pointed value
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const char* p = "Hello\n";

p = "World\n"; //works as pointer is not const

++p; // works and *p* is not pointing to 'W' now but points to some next memory location ('o')
cout << *p << "\n";

//++(*p); //not work as const char means char value is const and *p* cant modify pointed value
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Question is why you think *p* is not behaving like *p1* ?

Answer 2

I'm not quite sure what you mean?
const char* functions the same as const int*.

In this case, 'char*' or 'char* const' works a little different than 'int*' or 'int* const' only because the pointed-to string is stored in read only memory, so you can't assign it a different character. If that is what you mean.

Answer 3

char* name = "blah blah"; <= this will compile as normal but if you try to modify it at run time, your prog will fail.

const char* name = "blah blah" ; <= this will NOT even compile if your code tries to modify it.

Answer 4

Thanks rodwynnejones , Dennis and Arsenic

I was confused about what is const in case of const char*

Char* is nothing but string kind of and hence "hello" string is constant.. so can't modify the same like Hello or Dello

In short this we should define as const char* as what we assigned initially is in code or constant section