UNIX for Dummies Questions & Answers

Your command is working fine for the type of file you gave as an example. But consider the file I have given as an example in such a case the command

count=1
AWK -F"|" '$1 ~ /'$count'/ {printf $4}' file1

will give the output for all the numbers starting with 1 (eg 1, 100, 101..etc)in the first column of the table! Since ~ gives an approimate matching this won't help. I need an exact watch which is possible with ==

Hello,

If you want to get the line starts with 100 means, you have to give like this :
count=100
awk -F"|" '$1 ~ /'$count'/ {print $3} file1

you can also give the search string like this :
$ search_string="aaa"
$ awk -F"|" '$2 ~ /'$search_string'/ {print $3} file1

count is not the line number. It's a search string only.
Hope you got better idea.

I have understood your point of view btu I guess I couldn't properly express you with my problem. So, I am writing a part of my program underneath

my file is something like this with tabs and whitespaces inbetween and delimited by "|'

CAT file1
abc |123 |234
bcd |345 |456
cde |567 |678

Now my program is something like this:

start_cnt=1
end_cnt=200
while [ start_cnt -le end_cnt ]
do
var1=`AWK -F"|" '...........{ printf $2 }' file1`
echo "$var1" >> file2
start_cnt=`expr $start_cnt + 1`
done
echo "Finished file appending"

Now I don't know what to write in the space provided in the AWK command such that it will use the start_cnt as the incrementing variable starting with line 1 as start_cnt=1 and line 200 as start_cnt=200 and on each step will append the value at position $2 to file2

I hope now I could make you understand my problem!

I think no need to use the loop in here.
You can just use the awk command and write the output to a file like this :
search_string="xxx"
awk -F"|" '$1 ~ '/$search_string/' { printf $2 }' file1 > file2

Yes, that can be done but for a long table if you have to search each element of the field, you will require a lot of code.
Whereas I am looking for a very genaralised pattern!

It's a bit expensive to scan the ENTIRE input file on EVERY iteration of the loop, but...
Given udi.txt:

Code:

abc |123 |234
bcd |345 |456
cde |567 |678

Code:

#!/bin/sh

start_cnt=1
end_cnt=200
while [ "${start_cnt}" -le "${end_cnt}" ]
do
   var1=`awk -F"|" -v fnr="${start_cnt}" 'FNR == fnr { printf $2 }' udi.txt`
   echo "$var1"
   start_cnt=`expr $start_cnt + 1`
done
echo "Finished file appending"

Thanks a lot. It worked! I tried that way but I was using NR in place FNR.
Thanks again!