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The type size_t generally covers the entire address space. The C Standard, Annex K (normative), "Bounds-checking interfaces," introduces a new type, rsize_t, defined to be size_t but explicitly used to hold the size of a single object [Meyers 2004]. In code that documents this purpose by using the type rsize_t, the size of an object can be checked to verify that it is no larger than RSIZE_MAX, the maximum size of a normal single object, which provides additional input validation for library functions. See STR07-C. Use the bounds-checking interfaces for remediation of existing string manipulation code for additional discussion of C11 Annex K.
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Related Guidelines
| CERT C++ Secure Coding Standard | INT01-CPP. Use rsize_t or size_t for all integer values representing the size of an object |
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