I must say I an not a pro in Ubuntu-stuff. I would like to set the Seti@Home-screensaver, via Boinc, on my Ubuntu 14.04. For that I installed xscreensaver and I read on boin.barkeley.edu the advise:

"add the following to the 'programs' preference in your .xscreensaver file:
GL: boincscr -root \n\"

Typing "which xscreensaver" gave me "/usr/bin/xscreensaver". But I cannot find the ".xscreensaver" file in the "/bin" directory. I typed in terminal "emacs xscreensaver" and a blank file opened. Could it be that I have to create it? Since I don't know how to do it, can I instead access another file and do the change there?
Can somebody who has done this before walk me through the steps?

I see this is a fairly old post but it went unanswered. You may have already found this out but....
'xscreensaver' is the actual program file which is in /usr/bin/ but the '.xscreensaver' (note the leading period) is it's preferencces file located in your home directory. The leading period indicates that it is a hidden file so you have to tell your file manager to view hidden files before you will be able to see it. If it does not exist in your home directory just create it by using a text editor and putting the line you indicate inside it and saving it in the top level (root) of your home directory, and be sure not to forget the leading period in the filename.
I do not have xscreensaver installed at the present time as this is a new installation, but pull up a terminal and type 'man .xscreensaver' to get the layout of the file to find the proper way to indicate the 'programs' section. It may be as simple as putting the word 'programs' on a line with your line underneath, but they might be other ways of indicating the sections. It's been a long time since I've used xscreensaver so I'm not sure of the layout of it's preferences file.
Hope this helps.

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Jim

Some people plan their life out and look back at the wealth they've had.
Others live life day by day and look back at the wealth of experiences and enjoyment they've had.

As an addition to my earlier post, you might look under /usr/share/xscreensaver for example files or search in the /etc directory for 'xscreensaver.rc' which is the system-wide settings file. It could be located either /etc, /etc/xscreensaver, or /etc/preferences. (If under /etc/preferences it will already be named '.xscreensaver'.) If you find it simply open it in a text editor,, add the line you mentioned in the right place and save it in your home directory as '.xscreensaver'. The version in the /etc directory may be preferable as any modifications for your particular setup should already be included in that version, while the ones in /usr/share will be generic files.
This is to make the SETI screensaver only show for your user. If you want to make it visible for any user on your computer, simply add the line to the 'xscreensaver.rc' file in the /etc directory overwriting the original. Don't change it's name in this situation. (You must be logged in as 'root' to make changes to this file.)

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Jim

Some people plan their life out and look back at the wealth they've had.
Others live life day by day and look back at the wealth of experiences and enjoyment they've had.