UNIX for Dummies Questions & Answers

x=$1" "$2

at the very begining $1(field 1) then space and $2(field 2 ) are getting stored in variable x.
then the "for loop" concept is here started from the third field unwards and should be compared for the "if condition"if ($i~"^aaa"||$i~"^bbb"||$i~"^ccc"){$i=substr($i,1,3);x=x" "$i} (which is if the particular field will be starting by "aaa" or "bbb" or "ccc") then make the $i which is the corrent field to it first 3 character(suppose a field is aaa#6 then the first 3 character which is "aaa" will be stored in$i) and the x is again modified to x" "$i(which is nothig but its content with a space and the current field ) and finally print x does the printing of the content of x which is nothing but the first two field of the lines and all the matches of aaa bbb ccc.


you can remove the red code which also give the same output

Code:

awk '{x=$1" "$2; for (i=3;i<=NF;i++){ if ($i~"^aaa"||$i~"^bbb"||$i~"^ccc"){$i=substr($i,1,3);x=x" "$i}}; print x;x="" }' infile |awk 'NF>2 {print $0}'|sed 's/\//./3g
s/\///g'

regards,
Sanjay