sed + how to remove the last string after specific character

Question

how to remove the last string after "." character include the "." character itself

implementation can be with sed under Linux/Solaris operation system

example of IP address before change

      192.9.200.1     ( need to remove the .1 )

expected results

      192.9.200

other example

      100.2.2.101FFF

expected results

      100.2.2

Solution 1

maybe with cut instead of sed?

echo "10.10.10.5" | cut -d. -f-3

if it has to be sed

echo "10.10.10.5fsdfdsf" | sed -e 's/\.[^\.]*$//'

Solution 2

Why sed? How about manipulating with bash parameter expansion?

var="192.168.200.1"
echo ${var%.*}

192.168.200

Comments

[Johannes]

just a side note, but using sed this way is advocating backtracking on the regex engine which is slow in case you need to change a huge amount of records on a regular basis.