Shell Programming and Scripting

#Outer Loop to process mainList array elements
for i in "${mainList[@]}"
do
#Inner Loop to to process cPList array elements
for j in "${i[@]}" **

#!/usr/bin/ksh
begin=0
i=0
nump=5 # number of accounts per processing, increase or decrease

# plain text file with account1 to account39, each in new line is created named 'accs.txt'
# for test input, fill array 'accounts' with results

while read accs 
do
	accounts[$i]=$accs
	i=$(($i+1))
done < accs.txt

# number of iterations required for processing, we divide total number of elems in array with $nump
ITT="$(( ${#accounts[@]} / $nump ))"

for (( f=$begin; f<=$ITT; f++ ))
do
	# If utilities used support multiple accounts input, a for loop is not neccesary.
	# echo "${accounts[@]:$begin:$nump}"
	# this takes care of reminder as well
	for account in "${accounts[@]:$begin:$nump}"
	do
		echo "work (backup, sftp, cleanup) against for $account"	
	done
	begin=$(($begin+$nump))
	sleep 1 # we sleep here 1 second after 5 accounts have been processed, you might not.
done

#!/bin/bash
# bash or ksh93
nump=5 # number of accounts per processing, increase or decrease

# plain text file with account1 to account39, each in new line is created named 'accs.txt'
# for test input, fill array 'accounts' with results
na=0
while read accs 
do
  accounts[na]=$accs
  na=$((na+1))
done < accs.txt

for (( begin=0; begin<na; begin+=nump ))
do
  # If utilities used support multiple accounts input, a for loop is not neccesary.
  # this takes care of reminder as well
  for account in "${accounts[@]:begin:nump}"
  do
    echo "work on $account"
  done
  echo "group action for ${accounts[@]:begin:nump}"
  sleep 1 # we sleep here 1 second after 5 accounts have been processed, you might not.
done

#!/bin/sh
# any Posix sh
nump=5 # number of accounts per processing, increase or decrease

# the final group action is after the loop, so we put it in a function
group_action(){
  echo "group action on
$accounts"
  sleep 1
}

# plain text file with account1 to account39, each in new line is created named 'accs.txt'
i=0 na=0 accounts=""
while read account 
do
  accounts=$accounts${accounts:+"
"}$account
  echo "work on $account"
  if [ $((i+=1)) -eq $nump ]
  then
    group_action
    accounts=""
    i=0
  fi
  na=$((na+1))
done < accs.txt
[ $i -ne 0 ] && group_action