Just discovered moreutils after searching for “cat file sort and write to same file”.
StackExchange told me that sort actually has an option to pseudo edit
files “in-place” with the -o, --output options. But one of the more
intersting (pun intended) google results described sponge found in
moreutils.
Where you can do nifty things like:
$ sort conquest_eligible.txt | sponge conquest_eligible.txt