I recently re-installed my system OS (Ubuntu 16.04LTS) and it caused some parts WW to stop working. Right now I'm trying generate a table of random numbers and the conversion from latex to image is failing with
cd /opt/webwork/webwork2/tmp/ImageGenerator.XHKZhGL6 && /usr/bin/dvipng -bgTransparent -D120 -q -depth equation > dvipng.out 2> dvipng.err returned non-zero status 32512: Inappropriate ioctl for device at /opt/webwork/pg/lib/WeBWorK/PG/ImageGenerator.pm line 413.
ImageGenerator: preserved temp files in working directory '/opt/webwork/webwork2/tmp/ImageGenerator.XHKZhGL6'.
I assume this is a permission error. In what folder are these png files supposed to be stored?
Old images (generated before the OS crisis) still work, it's only new ones (with new random seeds) that cause an error.