If you are getting this problem with sudo and not gksu you should open a new ticket.
** Package changed: sudo (Ubuntu) => gksu (Ubuntu) ** Changed in: gksu (Ubuntu) Status: Confirmed => Invalid -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to sudo in Ubuntu. https://bugs.launchpad.net/bugs/1321704 Title: fcntl error with gksu Status in “gksu” package in Ubuntu: Invalid Bug description: I'm using Ubuntu 14.10 dev with gksu 2.0.2-6ubuntu2 and after making today a dist-upgrade I'm getting the following error if I want to start gksu: sworddragon@ubuntu:~$ gksu pcmanfm ** (gksu:1849): CRITICAL **: fcntl error ** (gksu:1849): WARNING **: Lock taken by pid: -1. Exiting. Edit: Downgrading linux-image-generic from version 3.15.0.1.2 0 to version 3.13.0.24.29 0 fixes the issue. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gksu/+bug/1321704/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp