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RXTX info

RXTX is basically an open source JavaComm API implementation. Older versions used the javax.comm namespace, but the later versions have been changed to for various reasons. Any Java programs using serial IO can probably be easily converted to use RXTX by just replacing the import javax.comm lines with

It is available at The latest "stable" version is 2.1.7-pre17, but I was unable to get it working (segfaults). I compiled a snapshot version from source. You can get it from It's pretty easy to make and install. Make sure your JAVA_HOME is set correctly, and that you can write to the directory. Then
./configure --disable-lockfiles
make install

The –disable-lockfiles option prevents RXTX from attempting to create lock files in /var/lock. The lab machines do not allow normal users to do this, so it's important to disable them if you're going to use it on a machine you don't have root on.

Note for uMiddle people: In our uMiddle shared directory, the IBM 1.4 JDK contains the IBM version of javax.comm, and the Sun 1.5 JDK has my version of RXTX installed.

Another note: This is NOT supposed to co-exist with javax.comm, so I wouldn't try it. No guarantees that this will work on any particular implementation, but I'm currently using it on Sun 1.5.0_03.

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