strings

• feature

    $ greedy match     : 1#2#3#4 -> 1#2#3
    $ non greedy match : 1#2#3#4 -> 1
    $ last column      : 1#2#3#4 -> 4
            $ last 3 line
            $ first 3 line
            $ all but first 3 lines
            $ all but last 3 lines
  

• sed

    $ sed -e 's/\(.*\)#.*/\1/'
    $ sed -e 's/\([^#]*\)#.*/\1/'
    $ sed -e 's/.*#//'
  

• perl

    $ perl -pe 's/(.*)#.*/\1/'
    $ perl -pe 's/(.*?)#.*/\1/'a
    $ perl -pe 's/.*#(.*)/\1/'
    $ perl -lane 'print $F[-1]' (alt. last column)
  

• ruby

    $ ruby -pe "gsub(/(.*)#.*/,'\1')"
    $ ruby -pe "gsub(/(.*?)#.*/,'\1')"
    $ ruby -pe "gsub(/.*#(.*)/,'\1')"
  

• awk

    $ awk -F"#" '{{for (i=1; i<NF-1; i++) printf $i "#"} print $(NF-1)}'
    $ awk -F"#" '{print $1}'
    $ awk -F"#" '{print $NF}'
  

• bash

    $ ???
    $ ???
    $  while IFS="#" read -r -a line; do
        nb=${#line[@]}
        echo ${line[$((nb - 1))]}
       done
  

• other tools

    $ cut -F# -f1
    $ ???
    $ rev | cut -F# -f1 | rev