Help with AWK Please

Shell Programming and Scripting
1

I have a file like

ABCD_1_0
ABCD_25_6
ABCD_326_12
ABCD_10_3

where ABCD (can be something else) but always 4 characters followed by a underscore and then numbers that go from 1-9999 and then followed by underscore and then a number that can go from 0-100

from this file I want to strip anything from second underscore onwards i.e. I need a file

ABCD_1
ABCD_25
ABCD_326
ABCD_10

Please help

2 
cat tawk.dat
ABCD_1_0
ABCD_25_6
ABCD_326_12
ABCD_10_3

awk -F_ '{ print $1"_"$2 }' tawk.dat
ABCD_1
ABCD_25
ABCD_326
ABCD_10
3

by sed..

sed 's/\(...._[0-9]\{,4\}\)_.*/\1/g' inputfile > outfile
4 
sed 's/\(_[^_]*\).*/\1/' infile

cut -d_ -f-2 infile
1 Like
5

As one of the many possibilities:

>cat 1
ABCD_1_0
ABCD_25_6
ABCD_326_12
ABCD_10_3

>cat 1 | awk 'match($0, /_[0-9]+/) { print substr($0,1,RSTART+RLENGTH-1)}' 
ABCD_1
ABCD_25
ABCD_326
ABCD_10
6

Thanks for a tremendous response, I now need to learn awk and sed. Thanks a million again. God Bless.