为什么我不能修改 c 中的字符串文字？

Question

I am trying to understand the reason behind not being able to modify a string literal in C.

Why is the following illegal in C?

char* p = "abc";
*p = 'd';

Answer 1

From the C89 Rationale, 3.1.4 String literals :

String literals are specified to be unmodifiable. This specification allows implementations to share copies of strings with identical text, to place string literals in read-only memory, and perform certain optimizations. However, string literals do not have the type array of const char, in order to avoid the problems of pointer type checking, particularly with library functions, since assigning a pointer to const char to a plain pointer to char is not valid. Those members of the Committee who insisted that string literals should be modifiable were content to have this practice designated a common extension (see F.5.5).