On Wed, Nov 25, 2009 at 8:15 PM, Dylan Beaudette <debeaude...@ucdavis.edu> wrote: > Hi, > > I am trying to transition a system based on dynamic image generation (via R) > from our development system to a production environment. Our R script > functions as expected when run by a regular user. However the script dies > when calling the png() function, when started by the webserver user. > > Here are some details > >>sessionInfo() > R version 2.9.2 (2009-08-24) > i686-pc-linux-gnu > locale: > C > attached base packages: > [1] stats graphics grDevices utils datasets methods base > > The script gets to this line: > > png(file=filename, width=600, height=400) > > and then dies. It leaves an empty PNG file where it should be, however it > never finishes the file. If > > I replace png() with pdf() an output file is generated and closed by dev.off() > as expected. > > It seems like the environment is setup just as when started by a regular user, > specifically the LD_LIBRARY_PATH variable. > > This behavior suggests that R is encountering an error, and stopping. However > there is no reporting of the error. Is there any way to get more verbose > error reporting?
How is R run from your web server? Does it start a new R process or is it an apache module thing with a dynamically linked R (if such a thing even exists)? Can't figure out how you could get more error reporting without knowing that - you need to see where stderr is going, possibly to the apache error.log file - have you looked there? Have you tried a trivial png generating example, just a three liner: png(file="/tmp/wherever/foo.png") plot(1:10) dev.off() just in case it's something else previous in your script that's breaking things. In the old days of R you needed an X11 display connection to do PNG graphics, but that was fixed before 2.9, I think. Try it interactively but unset the DISPLAY variable first: export -n DISPLAY R > png(... etc etc) Does that work? Barry ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
