Calibre Error Opening PDF File

Recently I'm trying to manage by ebooks collection by using Calibre. From my previous usage with Calibre and previous Slackware, I haven't a single problem when opening an ebook with pdf type. But now when I'm opening pdf ebook with Calibre it always open it with Karbon. Well, this really a big mess, how can I read an ebook with svg editor ?

That's turn out to be a problem with mime type association. With some googling I've found the solution for it:

First, find the default application when opening pdf file by using the following command:

 xdg-mime query default application/pdf  

with result:

 kde4-karbon.desktop  

From here I know that my system defaulting to karbon when opening a pdf file.

Second,  I must change it to my pdf application which is Okular with the following command:

 xdg-mime default okular.desktop application/pdf  

Now my Calibre happily open a pdf file with Okular.


sources of inspiration:
1.xdg-open
2.How to properly and easy configure `xdg-open` without any enviroment?