Shell Programming and Scripting

1,A,USA,0
2,B,GERMANY,0
3,C,IND,IA,0
4,D,CH,INA,0

$ printf "%s\x01" {1..31} > infile
$ printf "32\n" >> infile
$ printf "%s\x01" {1..5} 6{A..E} {7..31} >> infile
$ printf "32\n" >> infile

 
echo "1,A,USA,0" > test_input.dat
echo "2,B,GERMANY,0" >> test_input.dat
echo "3,C,IND,IA,0" >> test_input.dat
echo "4,D,CH,INA,0" >> test_input.dat
 
sed -i 's/,/|/' test_input.dat                        ## for first delimiter ##
sed -i 's/,/|/' test_input.dat                        ## for 2nd delimiter ##
rev test_input.dat  > test_input.dat_rev       ## reversing the record, since there might be multiple additional delimiters in the problematic column ##
sed -i 's/,/|/' test_input.dat_rev                 ## for the last delimiter in the original record ##
sed -i 's/,//g' test_input.dat_rev                ## this removes the additional delimiters in the required column  ##
rev test_input.dat_rev > test_input.dat      ## revering the file to its original form ##
sed -i 's/|/,/g' test_input.dat ## replacing the new delimiters with original delimiters ##

awk -F$(printf '\x01') '
NF>32{
   E=NF-32
   for(i=7;i<7+E;i++) $6=$6$i
   for(i=7;i<=32;i++) $i=$(i+E)
   NF=32
} 1' OFS=$(printf '\x01') infile