Hi, I found that it does work, but you must specify an output file as pdftk doesn't overwrite. The message is definitely unclear. e.g. something like the following works for me
--- info=$(cat <<EOF InfoKey: Title InfoValue: The Title EOF ) echo "$info" | pdftk 'myfile.pdf update_info - output 'myfile.pdf~' mv 'myfile.pdf~ 'myfile.pdf' --- Another related issue is described in https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=788660 seems to persist; as far as I can tell, you can only update one item at a time, otherwise if you try to do, say, title and author at the same time, you get --- pdftk Warning: InfoKey: (Title) already loaded when reading new InfoKey: (Author) -- skipping newer item --- Using multiple separate invocations of update_info with just one InfoKey/InfoValue at a time (each time moving temporary new output file back to the original) seems to work. -i
