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The next part of this page was provided by Rob Plevier, and describes his successful experience installing JMRI on OpenSUSE Linux. Most of the effort when into getting the Java communications library installed and working.
First I deleted all references to rxtx from my java directory as follows: rm /usr/lib/jvm/java/jre/lib/i386/rxtx* rm /usr/lib/jvm/java/jre/lib/ext/comm.jar rm /usr/lib/jvm/java/jre/lib/ext/RXTXcomm.jar Then I re-installed rxtx-2.0-7pre2 as follows 1. make sure there's a JAVA_HOME environment variable # echo $JAVA_HOME should display something like /usr/lib/jvm/java 2. add JAVA_HOME to the PATH # PATH=$JAVA_HOME/bin:$PATH 3. unpack rxtx # tar zxf rxtx-2.0-7pre2.tar.gz 4. install it # cd rxtx-2.0-7pre2 # ./configure during configure it asks you whether to run the script to place comm.jar in the appropriate directory. On a side note, when I specified the comm.jar that you sent me (the 28034 byte one) it told me it was a Windows version of comm.jar so I grabbed the one that I downloaded the second time which is 29411 bytes which I got from javacomm20-x86. I thought Macs ran a flavor of linux? Oh well. This is the file I used: -rw-r--r-- 1 root root 29411 2007-05-27 10:40 comm.jar # make # make install and everything ended up in /usr/lib/jvm/java/jre/lib/javax.comm.properties /usr/lib/jvm/java/jre/lib/ext/comm.jar /usr/lib/jvm/java/jre/lib/ext/RXTXcomm.jar /usr/lib/jvm/java/jre/lib/i386/librxtxParallel-2.0.7pre2.so /usr/lib/jvm/java/jre/lib/i386/librxtxParallel.la /usr/lib/jvm/java/jre/lib/i386/librxtxParallel.so /usr/lib/jvm/java/jre/lib/i386/librxtxSerial-2.0.7pre2.so /usr/lib/jvm/java/jre/lib/i386/librxtxSerial.la /usr/lib/jvm/java/jre/lib/i386/librxtxSerial.so and javax.comm.properties contains Driver=gnu.io.RXTXCommDriver with a line feed after it :^) some other notes.. openSuse has no lock group, only uucp, I edited my /etc/group file like this: uucp:x:14:robert and permissions on /dev/ttyS0 are crw-rw---- 1 root uucp 4, 64 2007-05-27 11:56 /dev/ttyS0 Essentially I think I'd been messing around with it for so long I had different versions of rxtx and comm.jar everywhere. At least I didn't have to reinstall Linux (again!). Lesson - make sure you follow the instructions. If I'd loaded commapi version 2 in the first place it would have been fine :^) instead I just grabbed the first one I saw on the sun site which was version 3.
Stephen Williams added a little more info about setting permissions:
The basic problem here is that you will need to add yourself to the appropriate groups both to open the serial devices (/dev/ttyS*) and to be able to create files in the lock file directory. This is another area where the RedHat-ish distributions (and Suse is in that camp) differ from the Debian/Ubuntu distributions. On your Suse system, do the following command: stevew@wallace:~/rxtx-2.0-7pre2$ ls -l /dev/ttyS* crw-rw---- 1 root dialout 4, 64 2008-02-10 17:08 /dev/ttyS0 crw-rw---- 1 root dialout 4, 65 2008-02-10 17:08 /dev/ttyS1 crw-rw---- 1 root dialout 4, 66 2008-02-10 17:08 /dev/ttyS2 crw-rw---- 1 root dialout 4, 67 2008-02-10 17:08 /dev/ttyS3 The output is from my own machine which runs Debian. Your system will likely have a different group name listed after the 'root' user. That is one of the groups you need to belong to. Then look at the permissions and group ownership of /var/lock (ls -al /var/lock and look at the entry for '.'). If there is a group other than root listed there, you need to belong to that group (it is often "uucp" or "lock"). Hope that helps.