Using Octave in a CGI script

[John W. Eaton]

On 10-Sep-1998, John Verzani <address@hidden> wrote:

| I've been working on a CGI script that allows students to use Octave
| via the web. To eliminate (I hope!) the possibility of a malicious
| student destroying the server it is running on, I am using a package
| called sbox which runs the script as a restricted user after issuing a
| chroot command. So, in theory, the system calls in octave only have
| access to the files I put into the new root directory. Basically I've
| put in perl, octave, gnuplot and whatever libraries these need to
| run. Everything seems to work well, except for one thing. Gnuplot
| doesn't work. I know this has something to do with running gnuplot in
| the chroot setting, as the script works when I don't care about
| security. If I try running Octave at the command line after a chroot
| command I get an error message of this type when trying to plot:

| ...

| My question is: what things need to be available to octave to create the
| subprocess that will allow gnuplot to run as the external plotter?

Do you have a /tmp directory in your private directory tree?  Octave
writes temporary data files there for gnuplot to plot.

For using Octave interactively via the web you might also look at
http://www.ma.utexas.edu/users/wfs/netmath/netmath.html.

jwe