Question

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What is the difference between char s[] and char *s in C?
Question about pointers and strings in C

I’m reading about the strings in C and I’m confused. I can “declare” strings in two ways:

char *str = "This is string";
char str2[20] = "This is string"; 

What is the difference between the two declarations? When would char str2[20] be preferred over char *str?

Answer 1

char *str = "This is string";

Puts the string in the constant data section (also known as .rdata) of the program.This data can’t be modified.

char str2[20] = "This is string";

In this type of declaration data is preferably stored in the stack area of the program, if declared inside the function scope and in data section if declared in global scope.This data can be modified.

So if you have a necessity to modify data then use the second approach.