핸들이 동기 작업을 지원하지 않습니다. 핸들이 중첩된 I/O용, 즉 비동기적으로 열려 있음을 나타내기 위해 FileStream 생성자의 매개 변수를 변경해야 할 수 있습니다.
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English version
Handle does not support synchronous operations. The parameters to the FileStream constructor may need to be changed to indicate that the handle was opened asynchronously (that is, it was opened explicitly for overlapped I/O).