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<title>The Java Language Specification The Package java.io </title>
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<center><h1>22.26 The Class <code>java.io.FileDescriptor</code></h1></center>
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A <code>FileDescriptor</code> is an opaque representation of a connection to an actual file
in a file system, or to a network socket, or to another source or sink of bytes. The
main practical use for a file descriptor is to create a <code>FileInputStream</code> <a href="javaio.doc2.html#28263">(§22.4.3)</a>
or <code>FileOutputStream</code> <a href="javaio.doc14.html#29525">(§22.16.3)</a> to contain it.
<p><pre><a name="29891"></a>public final class <code><b>FileDescriptor</b></code> {
<a name="29892"></a> public static final FileDescriptor <code><b>in</b></code> = ...;
<a name="29893"></a> public static final FileDescriptor <code><b>out</b></code> = ...;
<a name="29894"></a> public static final FileDescriptor <code><b>err</b></code> = ...;
<a name="29895"></a> public boolean <code><b>valid</b></code>();
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<p><font size=+1><strong>22.26.1 </strong> <code>public static final FileDescriptor <code><b>in</b></code> = ...</code></font>
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A file descriptor for the standard input stream. Usually, this file descriptor is not
used directly, but rather the input stream known as <code>System.in</code> <a href="javalang.doc17.html#14130">(§20.18.1)</a>.
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<p><font size=+1><strong>22.26.2 </strong> <code>public static final FileDescriptor <code><b>out</b></code> = ...</code></font>
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A file descriptor for the standard output stream. Usually, this file descriptor is not
used directly, but rather the output stream known as <code>System.out</code> <a href="javalang.doc17.html#14131">(§20.18.2)</a>.
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<p><font size=+1><strong>22.26.3 </strong> <code>public static final FileDescriptor <code><b>err</b></code> = ...</code></font>
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A file descriptor for the standard error output stream. Usually, this file descriptor
is not used directly, but rather the output stream known as <code>System.err</code>
<a href="javalang.doc17.html#14132">(§20.18.3)</a>.
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<p><font size=+1><strong>22.26.4 </strong> <code>public boolean <code><b>valid</b></code>()</code></font>
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If this <code>FileDescriptor</code> is valid (represents an active connection to a file or other
active I/O connection), then the result is <code>true</code>. Otherwise, the result is <code>false</code>.
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<font size=-1>Java Language Specification (HTML generated by Suzette Pelouch on February 24, 1998)<br>
<i><a href="jcopyright.doc.html">Copyright © 1996 Sun Microsystems, Inc.</a>
All rights reserved</i>
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Please send any comments or corrections to <a href="mailto:doug.kramer@sun.com">doug.kramer@sun.com</a>
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