[Rxtx] read() not blocking?

[Knute Johnson]

So I've redone my tests and specifically set the receive timeout and 
receive threshold states.

receiveTimeoutDisabled() and receiveThresholdDisabled()

import java.io.*;
import java.text.*;
import java.util.*;
import gnu.io.*;
//import javax.comm.*;

public class test {
    public static void main(String[] args) throws Exception {

        CommPortIdentifier cpi = 
CommPortIdentifier.getPortIdentifier("COM1");
        SerialPort sp = (SerialPort)cpi.open("test",2500);
               
        // set serial port parameters
        sp.setSerialPortParams(9600,SerialPort.DATABITS_8,
        SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);
        sp.setFlowControlMode(SerialPort.FLOWCONTROL_NONE);

        // both receive timeout and receive threshold disabled
        sp.disableReceiveTimeout();
        sp.disableReceiveThreshold();

        System.out.println("isReceiveThresholdEnabled: " +
         sp.isReceiveThresholdEnabled());
        System.out.println("isReceiveTimeoutEnabled: " +
         sp.isReceiveTimeoutEnabled());

        InputStream is = sp.getInputStream();

        SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
        System.out.println("Started "+sdf.format(new Date()));

        while (true) {
            int n = is.read();
            System.out.println(sdf.format(new Date())+" "+n);
        }
    }
}

C:\com\knutejohnson\redrock\race>java test
Stable Library
=========================================
Native lib Version = RXTX-2.1-7
Java lib Version   = RXTX-2.1-7
isReceiveThresholdEnabled: false
isReceiveTimeoutEnabled: false
Started 12:06:48
12:06:48 -1
12:06:48 -1
12:06:48 -1
12:06:48 -1
12:06:48 -1
12:06:48 -1
12:06:48 -1
12:06:48 -1
12:06:48 -1
12:06:48 -1
12:06:48 -1
12:06:48 -1

Note that it returns very quickly from the read, many times per 
second.  This should block yes?

Next is:

enableReceiveTimeout(Integer.MAX_VALUE)  disableReceiveThreshold()

import java.io.*;
import java.text.*;
import java.util.*;
import gnu.io.*;
//import javax.comm.*;

public class test {
    public static void main(String[] args) throws Exception {

        CommPortIdentifier cpi = 
CommPortIdentifier.getPortIdentifier("COM1");
        SerialPort sp = (SerialPort)cpi.open("test",2500);
               
        // set serial port parameters
        sp.setSerialPortParams(9600,SerialPort.DATABITS_8,
        SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);
        sp.setFlowControlMode(SerialPort.FLOWCONTROL_NONE);

        // both receive timeout and receive threshold disabled
        sp.enableReceiveTimeout(Integer.MAX_VALUE);
        sp.disableReceiveThreshold();

        System.out.println("isReceiveThresholdEnabled: " +
         sp.isReceiveThresholdEnabled());
        System.out.println("isReceiveTimeoutEnabled: " +
         sp.isReceiveTimeoutEnabled());

        InputStream is = sp.getInputStream();

        SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
        System.out.println("Started "+sdf.format(new Date()));

		while (true) {
            int n = is.read();
            System.out.println(sdf.format(new Date())+" "+n);
        }
    }
}

C:\com\knutejohnson\redrock\race>java test
Stable Library
=========================================
Native lib Version = RXTX-2.1-7
Java lib Version   = RXTX-2.1-7
isReceiveThresholdEnabled: false
isReceiveTimeoutEnabled: true
Started 12:09:11
12:09:51 -1
12:10:31 -1
12:11:11 -1
12:11:51 -1
12:12:32 -1
12:13:12 -1

Note the approximately 40 second timeout when Integer.MAX_VALUE 
should yield about 562 hours.

I did just find something interesting, a timeout setting of 65535 
gave a 1:26 timeout.  I'm trying 3,600,000 now to see if it will be 
close to an hour.

Any suggestions of what to try next would be great.

Thanks,

-- 
Knute Johnson
Molon Labe...