Unix cut command to extract string from left side post 2nd dilimiter from right

Question

how can the cut command return value left to 2nd last delimiter starting from the right side.

$ echo 'qwertyuiop.abcdefgh.1234567890.txt' | cut -d '.' -f 1,2
qwertyuiop.abcdefgh
$ echo 'qwertyuiop.1234567890.txt' | cut -d '.' -f 1,2
qwertyuiop.1234567890
$ 

expected output for both

qwertyuiop.abcdefgh

qwertyuiop

Answer 1

You can reverse your string with the rev command and then cut from the third field to the end, reversing at the end.

$ echo 'qwertyuiop.abcdefgh.1234567890.txt' | rev | cut -d '.' -f 3- | rev
qwertyuiop.abcdefgh
$ echo 'qwertyuiop.1234567890.txt' | rev | cut -d '.' -f 3- | rev
qwertyuiop