For Linux and Mac OS X, the user.home + ".<name>" is all you need.
The point isn't "all you need", the point is trying to follow the standards for whatever OS your program is running on. You could put your save in
C:\Users\ZMan\GameName\player1.sv and call it good, but instead we put it in
%AppData%\GameName\player1.sv because it's cleaner and is what is expected on Windows. If you don't care about that then ya,
user.home + gameName works just fine. I was just looking for an AppData equivalent on Linux/OSX.
While we're on the topic of standards, and expected behaviour; there's one that I
*hate*.
<rant>
When games/applications put binary data (usually some sort of save file) in the designated documents folder. My Documents on XP, Documents on Vista/7/8, user.home/Documents on linux. And you can't even relocate the data half the time without breaking the associated app.
Its a super irritating habit that too many devs have. Thats what the %appdata% folder is
*for* !!!
</rant>