String literals vs array of char when initializing a pointer

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I think you’re confused because char *p = "ab"; and char p[] = "ab"; have similar semantics, but different meanings.

I believe that the latter case (char p[] = "ab";) is best regarded as a short-hand notation for char p[] = {'a', 'b', '\0'}; (initializes an array with the size determined by the initializer). Actually, in this case, you could say "ab" is not really used as a string literal.

However, the former case (char *p = "ab";) is different in that it simply initializes the pointer p to point to the first element of the read-only string literal "ab".

I hope you see the difference. While char p[] = "ab"; is representable as an initialization such as you described, char *p = "ab"; is not, as pointers are, well, not arrays, and initializing them with an array initializer does something entirely different (namely give them the value of the first element, 0x61 in your case).

Long story short, C compilers only “replace” a string literal with a char array initializer if it is suitable to do so, i.e. it is being used to initialize a char array.

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