Can you add an option to eix to "use emerge-delta-webrsync" instead of "emerge --sync"? Since it depend on app-portage/emerge-delta-webrsync, you can use a patch file that will be applied only if a useflag is used. As 2nd choice you can add a commented line that will be uncommented using sed command if a useflag is used: suppose to call '-x' the option and 'delta' the useflag, in eix-sync you can add ### x) EMERGECMD=("emerge-delta-webrsync");; while in ebuild if use delta; then sed -i 's,### , ,' eix-sync fi
I suppose -x would be enough. Use flags are ot supposed to be used inflationary
In eix' current svn trunk flag -W is added to eix-sync for emerge-delta-webrsync (in order to be consistent with -w for emerge-webrsync). In addition, more general flags -c -C are added which allow using any other command or additional options. Also a flag -M is added for "strange" local "emerge --sync" commands.
Change is in the Christmas release (0.8.4).