Locate should never give a 'fatal error'. The worst it should do is
return nothing and put you back to the command prompt again. Even if
you do a *.* search it should just produce a scrolling screen of files
as it lists everything, and if you do get that then [CTRL]+[C] will
stop it.

What happens if you just type locate with nothing for it to search ?
You should get a message that no pattern was specified.