I was about to write an article explaining how you can use Terminal and the Unix chmod command to change the file permissions of an epub, made necessary because when you uploaded your epub to Lulu, their wizard would shoot back a nasty message that there was a problem with permissions. But either Lulu fixed the wizard or one of the calibre updates fixed the permissions; all I know is that I no longer need do the following:
In calibre, tweak the epub (Command-click in calibre’s list), which will open a window on your desktop that essentially explodes the individual files that made up that epub.
Then open Terminal (you’ll find it in the Utilities folder inside your Applications folder) and type chmod 7xx (include a space after the 7xx).
I am sorry that I can’t remember what were the exact permissions that Lulu wanted. Based on this Sigil discussion, I think the desired permissions are 644 for files and 755 for directories. I played it loose and dangerous and just applied 777, which meant I didn’t have to drag folders separately from files.
Then drag the contents of the exploded folder onto the Terminal window. Terminal will then apply the chmod changes.
Back in calibre, rebuild the epub, although I think calibre does that automatically when you quit.
Oh wait, I just wrote the article I said I wouldn’t need to write. Well, maybe these file permission problems will surface again and this will be relevant again.