How to edit the PDF file directory under Linux

At present, I use the system LinuxMint, before the hard drive is not bad when the Foxit reader and okular to view the PDF file, but later found that Foxit reader to eat CPU, and now after the solid-state drive only 120G free space, So only the OKUALR.

A more deadly problem is that some PDF files need to modify the directory (in Foxit reader called bookmarks , okular called contents, literal translation is the directory ), but Okular does not seem to support the modification of the directory. But do not want to install Foxit Reader (just to modify the directory). Remember where you've seen it, someone (joking) that you're editing a PDF directly with Vim. So with the curiosity to open the PDF file with vim, although garbled, but still can see the structure, changed the directory, and then open unexpectedly with Okula really can use!

New skills!

How to edit the PDF file directory under Linux