Auto save cannot be disabled in OS X Lion. There are a few things you can do that work around it a little, but don't seem to resolve the problem completely:
- For individual documents, "lock" the document by clicking the little icon in the center of the title bar and choosing lock.
- System wide (doesn't work for every app), go to System Preferences, select General, then uncheck "Restore windows when quitting and re-opening apps."
- Use a script to delete the versions file(s) periodically, or on shutdown.
- Use a script to delete the versions directory on startup, thus preventing apps from storing versions in the first place
For the third option, one possible script is:
--{code}
--[SCRIPT deleteRevisions]
my deleteRevisions(path to startup disk as text)
-- my deleteRevisions("Aluice-500-Lion:")
on deleteRevisions(leVolume)
local leDossier, cheminUnix
set leDossier to leVolume & ".DocumentRevisions-V100:"
set cheminUnix to quoted form of POSIX path of leDossier
-- do shell script "stat -F " & cheminUnix
--> "d--x--x--x 7 root wheel 238 Aug 7 11:21:07 2011 /.DocumentRevisions-V100//"
do shell script "chmod 700 " & cheminUnix with administrator privileges
-- do shell script "stat -F " & cheminUnix
--> "drwx------ 7 root wheel 238 Aug 7 15:47:00 2011 /.DocumentRevisions-V100//"
do shell script "rm -dfr " & cheminUnix with administrator privileges
--> ""
end deleteRevisions
--=====
--[/SCRIPT]
--{code}
Some users have reported that some apps use different app-specific directories and so the above doesn't work completely, but takes care of the simple apps.
For the fourth option, a startup script might be:
--{code}
--[SCRIPT deleteApplicationsState]
set leDossier to (path to library folder from user domain as text) & "Saved Application State:"
set cheminUnix to quoted form of POSIX path of leDossier
do shell script "chmod 700 " & cheminUnix --with administrator privileges"
do shell script "rm -dfr " & cheminUnix --with administrator privileges
--> ""
--=====
--[/SCRIPT]
--{code}
Again, it doesn't account for apps that store their versions elsewhere.