As a result, the 20 byte block allocated by the func function is lost and results in a memory leak.
结果，func函数所分配的20个字节的块就丢失了，并导致了内存泄漏。
3
The locale setting will cause the % ls format specifier in printf to call the wcsrtombs function in order to convert the wide character argument string into the locale-dependent multi-byte encoding.
语言环境设置会导致printf中的% l s格式说明符调用wcsrtombs函数以便于将宽字符的参数字符串转换成依赖语言环境的多字节编码。