Copying data to a buffer that is not large enough to hold that data results in a buffer overflow. Buffer overflows occur frequently when manipulating strings [Seacord 2013]. To prevent such errors, either limit copies through truncation or, preferably, ensure that the destination is of sufficient size to hold the character data to be copied and the null-termination character. This . C strings require a null character to indicate the end o the string, while the C++ basic_string template requires no such character. This rule is a C++-specific instance of STR31-C. Guarantee that storage for strings has sufficient space for character data and the null terminator.
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