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values stored in [...] objects of type
unsigned charshall be represented using a pure binary notation. (C11, Section 6.2.1 [ISO/IEC 9899:2011])
where a pure binary notation is defined as the following:
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CERT C++ Secure Coding Standard: STR00-CPP. Represent characters using an appropriate type
ISO/IEC 9899:2011 Section Section 7.1.1, "Definitions of terms," and Section 7.24, "String handling <string.h>"
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