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Java in a Nutshell

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The java.io Package

24.17 java.io.FileDescriptor (JDK 1.0)

This class is a platform-independent representation of a low-level handle to an open file or an open socket. The static in, out, and err variables are FileDescriptor objects that represent the system standard input, output, and error streams, respectively. There is no public constructor method to create a FileDescriptor object. You can obtain one with the getFD() method of FileInputStream, FileOutputStream, and RandomAccessFile.

public final class FileDescriptor extends Object {
    // Default Constructor: public FileDescriptor()
    // Constants
            public static final FileDescriptor err;
            public static final FileDescriptor in;
            public static final FileDescriptor out;
    // Public Instance Methods
        1.1  public native void sync() throws SyncFailedException;
            public native boolean valid();

Passed To:

FileInputStream(), FileOutputStream(), FileReader(), FileWriter(), SecurityManager.checkRead(), SecurityManager.checkWrite()

Returned By:

DatagramSocketImpl.getFileDescriptor(), FileInputStream.getFD(), FileOutputStream.getFD(), RandomAccessFile.getFD(), SocketImpl.getFileDescriptor()

Type Of:

DatagramSocketImpl.fd, FileDescriptor.err, FileDescriptor.in, FileDescriptor.out, SocketImpl.fd

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