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At compile time, string literals are used to create an array of static storage duration of sufficient length to contain the character sequence and a null-termination character. It is unspecified whether these arrays are distinct. The behavior is undefined if a program attempts to modify string literals but frequently results in an access violation because string literals are typically stored in read-only memory. See also undefined behavior 33 of Annex J of the C standard [ISO/IEC 9899:2011].
The returned value of the library functions strpbrk(), strchr(), strrchr(), wcspbrk(), wcschr(), and wcsrchr() and pointer to (or array of) const characters shall be treated as a string literal.
Do not attempt to modify a string literal. Use a named array of characters to obtain a modifiable string.
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