~ # grep ttmkfdir /var/lib/portage/world 
~ # emerge --noreplace ttmkfdir

These are the packages that would be merged, in order:

Calculating dependencies... done!

Total size of downloads: 0 kB

Nothing to merge; quitting.

~ # grep ttmkfdir /var/lib/portage/world 
~ # EMERGE_DEFAULT_OPTS="" emerge --noreplace ttmkfdir
Calculating dependencies... done!
>>> Recording x11-apps/ttmkfdir in "world" favorites file...
WARNING: AUTOCLEAN is disabled.  This can cause serious problems due to overlapping packages.

 * GNU info directory index is up-to-date.
 * IMPORTANT: 8 config files in '/etc' need updating.
 * Type emerge --help config to learn how to update config files.

~ # grep ttmkfdir /var/lib/portage/world 
x11-apps/ttmkfdir