What is the difference between const char .....

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What's the difference between const char *p, char const *p, and char * const p?

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The first two are interchangeable; they declare a pointer to a constant character (you can't change any pointed-to characters). char * const p declares a constant pointer to a (variable) character (i.e. you can't change the pointer).
Read these declarations ``inside out'' to understand them;

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