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Mike, You might try temporarily setting the script to use the "ps" driver instead of gf. The ps driver won't use the X display of course, so if that succeeds, then it would point to your X connection that gf is trying to connect to. If it fails, then there is a problem in the www-data environment for running the script. if a normal user succeeds when drawing to the Xvfb display, then the depth is correctly set as 8 bits. Otherwise, check that. Generally the Xvfb uses a host list or permissioning on who can draw to it. I don't know if there is any configuration for user access as well. Have you tried becoming the www-data user (eg su - www-data" so that you can run the script as the user that would be executing the cgi? That would determine if there are any permission problems- remember that gemglb.nts and last.nts need to be written too. Does the script cd to a working space that might have been worked in by the user executing the script first? Steve Chiswell Unidata User Support On Mon, 18 Mar 2002, Hardiman, Michael P wrote: > Hi folks, > > I've run into a very annoying problem recently in trying to use CGI and > Gempak (still using 5.4) to plot forecast soundings "on-demand." > Basically, what is going on is the script works perfectly when executed > in the shell by a normal user, but when you switch to CGI, it crashes > after calling the "gplt" function, and you end up getting stuck with a > defunct GF process. All variables are being passed correctly, gempak's > gdplot program is called correctly, it all comes down to trying to > create the gif file. > > Originally, we had been utilising a VNC session for creating the > graphics, but we suspected that there might be a permissioning problem > in that only one user is allowed to access the VNC session. When using > the CGI interface through the web, a (special?) user called "www-data" > executes the commands, etc. So we started using an Xvfb session running > on a random display (:8 I believe). Same problem. > > I'm convinced that this has something to do with the "www-data" being > some sort of "special" user that is running into permissioning problems > in trying to use the Xvfb display, or maybe there's something in the > gplt or gf function thats causing the problem. This is being run on a > Debian Linux 2.2 PC system, with a webserver called "Xitami," and as I > said before, Gempak 5.4. > > If anyone can shed some light on this, it would be greatly appreciated. > If it would help to see the script, I can send it on request. I don't > want to bog down the list with unnecessary attachments. > > Thanks. > -Mike >