Strings must contain a null-termination character at or before the address of the last element of the array before they can be safely passed as arguments to standard string-handling functions, such as strcpy() or strlen(). These functions, as well as other string-handling functions defined by the C Standard, depend on the existence of a the string's null-termination character to determine the length of a the string. Similarly, strings must be null-terminated before iterating on a character array where the termination condition of the loop depends on the existence of a null-termination character within the memory allocated for the string, as in the following example:
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