FileInputStream.read() blocks the whole JVM instead of just the calling thread.

Name: el35337 Date: 06/24/97


The following Daemon.java program:
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import java.io.*;

public
class Daemon
{
public static
void
main(String[] args)
{
        PrintStream out = System.out;
        out.print("main: Starting read thread...");
        out.flush();
        new Thread(new Reader(), "Reader").start();
        out.println("done.");
        out.println("main: Calling yield(). Note: Reader thread should block in
");
        out.println(" FileInputStream.read() call, so our thread should con
tinue...");
        Thread.yield();
        out.println("main: Now we are continuing...");
}
};

class Reader
        implements Runnable
{
public
void
run()
{
        PrintStream out = System.out;
        try {
                out.println("reader: Reading one byte...");
                new FileInputStream(FileDescriptor.in).read();
                out.println("reader: Read one byte.");
        }
        catch (IOException e) {
                e.printStackTrace();
        }
}
};

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when run using the following cmdline:

{ echo "Press ENTER to send one byte:" >&2; read; echo -n s; }|java Daemon

issues the following output:
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Press ENTER to send one byte:
main: Starting read thread...done.
main: Calling yield(). Note: Reader thread should block in
      FileInputStream.read() call, so our thread should continue...
reader: Reading one byte...

reader: Read one byte.
main: Now we are continuing...
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company - InterSoft Argentina S.A. , email - ###@###.###
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