The conversion function identified by handler requires as its argumentspointers to the input and output strings, along with the length of each. Thelengths must be determined separately by the application.

• 句柄所标识的转换函数需要指向输入和输出字符串的指针作为其参数,同时也需要这两者的长度。而长度必须由应用程序来分别指定。