KnotPlot is a No Go

Usually when people install KnotPlot and it doesn't run, one of two things are the problem.

KnotPlot can't find the KnotPlot home

If this is the problem, either you haven't installed the distribution or KnotPlot just can't find it. It will squack at you the following text:

*** Can't find KnotPlot home, things will not work! ***
*** You might need to specify a KNOTPLOT_HOME environment variable. ***

To make KnotPlot happy, make sure the distribution is there and that you've set the KNOTPLOT_HOME environment variable correctly.

Wrong or missing kp-thing file

This is the most common problem that people encounter. The distribution comes with a kp-thing specific to the Department of Computer Science at U.B.C. If you don't copy over the default version of kp-thing with the one that I send you, then KnotPlot will not run. Consider kp-thing to be your licence to run KnotPlot. To check to see if you just have the wrong file try running KnotPlot as follows:

knotplot -nog -debug

The -nog is for no graphics and the -debug will print out diagnostic information. If you don't have the correct kp-thing file installed, you'll get a bunch of strange messages, but it should include something like the following:

Checking licence file `kp-thing' in resource directory.
Looking for `/where/i/put/knotplot/resource/kp-thing'.
Found `kp-thing' alright, checking contents.
kp-thing: KnotPlot kp-thing file for Dept. of Computer Science, U.B.C

The first line and second lines tell you where it expects to find the kp-thing file. The third line tells you that it found the file where it expected to (you'll get a different error message if the file is missing). The last line indicates the domain that the kp-thing file is good for. If your output looks similar to the one above (i.e. it says kp-thing for U.B.C.), then you still have the original kp-thing file from the distribution in the resource directory. To fix this just copy the version of kp-thing that I emailed to you over the one in the above location and everything should work fine. One way to do this is the following:

If things still don't work after you've tried this step, then email me the output from running

knotplot -nog -debug

as well as any other information that might be relevant.

Directories or files can't be read

This would generally be a problem only if the files needed by KnotPlot are owned by somebody else on your system. For example, it might happen if the TAR distribution was unpacked by a super-user using the wrong umask. Or perhaps the kp-thing file is not readable by everyone. To fix, get the person who owns the files to go to the KnotPlot home and enter the command (under IRIX):

chmod -R ugo+rx *

The -R option is to recursively descend the directory tree. The command syntax may be slightly different on non-IRIX machines, check the man page if in doubt.

Go to the KnotPlot Site or Rob Scharein's main WWW page.