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The strtol(), strtoll(), strtoul(), and strtoull() functions convert the initial portion of a null-terminated byte string to long int, long long int, unsigned long int, and unsigned long long int representation, respectively.
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The strtol(), strtoll(), strtoul(), and strtoull() functions convert a null-terminated byte string to long int, long long int, unsigned long int, and unsigned long long int representation, respectively.
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