How to find out what's installed using installpkg
 

My problem is that I think I may have two versions of JDK, and the old one seems to haunt me.

check out /var/log/packages/

There are probably better ways, but that's what I'm used to doing.

To go a bit more in depth (if it's needed), you can run the following to find any JDK's that are currently installed (at least using the Slackware package management system).

I use QTGZManager to see what is installed and to update my system, it is very good. It can be found at slackbuilds.org site.

Should get you want you want as well, though I typically use /var/log/packages as well.

Have to check that out...
Thanks.

On my machine pkgtool is dead-slow.

Please elaborate as this statement is very vague.

Once in pkgtool, to display installed packages just choose "Remove" then press the key bearing the initial of the package.

For instance to find if JDK is there just press j (the letter, case doesn't matter), a few times until you find it (or not). That's not "dead slow" but rather almost instantaneous.

+1 for pkgtool. This is what I use and it works quickly.

pkgtool shouldn't be slow since technically it uses ncurses unless you have a VERY old computer.

If it's the JDK (development kit), it'll have the Java compiler command "javac". So:

$ which javac
(make note of the directory)
$ grep -l -i javac$ /var/log/packages/*

This will list all packages containing a filename ending in "javac" (case-insensitive). Don't search just for jdk* or jre* packages; there might be some other, differently-named Java implementations.

If it seems to run slow, that's primarily because the package-management file data gets ejected from cache fairly quickly, being (usually) rarely-accessed. Things will speed up while the contents are cached.

Stink Bad T42 with Slackware 14.1.

with root:
slackpkg generate-template slack

cat /etc/slackpkg/templates/slack.template

sorry

cat /etc/slackpkg/templates/slack.template | grep JDK