There’s probably a million flags to use for this, but for typical use:
sudo emerge --sync— analogous toapt update. Refreshes package overlays.- If prompted to (the sync will indicate it), update Portage first per the instructions in the message (usually
sudo emerge -a --oneshot sys-apps/portage). sudo emerge -a --update --deep --newuse --keep-going @world— analogous toapt upgrade-a: ask confirmation first--update: do an update, not a new install--deep: update the entire dependency tree--newuse: check for updates to useflags--keep-going: if a package fails to compile, move on to the rest of the updates instead of stopping dead (useful for overnight updates)@world: target everything presently installed