Shell Programming and Scripting

file1:
1,"aa,b",4
 
expected is the 2nd field:
aa,b
 
I tried the basic cut -d "," -f 2 file 1, this gave me
aa alone instead aa,b.

$ cat subquote.awk
{
        POS=1
        STR=""

        while(POS <= length($0))
        {
                SUB=substr($0, POS);
                OFF=match(SUB, /"[^"]*"/);

                if(OFF)
                {
                        BEF=substr(SUB, 1, RSTART-1);
                        M=substr(SUB, RSTART, RLENGTH);
                        AFTER=substr(SUB, RSTART+RLENGTH);

                        gsub(/,/, "\\,", M);

                        STR=STR BEF M;
                        POS+=(RSTART+RLENGTH)-1;
                }
                else
                {
                        STR=STR SUB;
                        POS=length($0)+1;
                }
        }

        print STR;
}

$ cat quotes.sh

#!/bin/sh

        # Convert "a,b" into "a\,b"
awk -f subquotes.awk datafile |
        # Read will take \, to be a literal , and others as separators
while IFS="," read A B C
do
        echo $B
done

$ ./quotes.sh

"aa,bb"

$

$ echo '1,"aa,b",4' | awk 'NR%2{gsub(/,/,";")}1' RS=\" ORS= 
1;aa,b;4

$ echo '1,"aa,b",4' | awk 'NR%2{gsub(/,/,";")}1' RS=\" ORS= | awk -F\; '{print $2}'
aa,b