File fetchrequest.sh

#!/bin/bash
while [ 10 -eq 10 ]

#Runs in a infinite loop checking request file at server B every second
do
if [ `env | grep -c lastCounter` = 1 ];then
newCounter=`curl -s http://serverB/requestFile.txt | tail -1 | cut -d: -f1`

#Reading request file at server B
param=`curl -s serverB/requestFile.txt | tail -1 | cut -d: -f2` #Extracting the request parameters
echo newCounter : $newCounter lastCounter : $lastCounter

#If there is a new request, sending a response back to the server B
if [ "$newCounter" != "$lastCounter" ]; then
echo "Need to send a response"
echo "Response URL : http://serverA/something.pl?action=something&param1&param2"

#Trimming of the response that needs to be send to serverB and storing it in a variable
output=`curl -s "http://serverA/something.pl?action=something&param1&param2" | grep 'cap\\|img' |
sed \ 's/<src>.*<\/src>//g;s/<cap>/\:/g;s/<\/cap>//g;s/<img>/\:/g;s/<\/img>//g'`
echo "Response received : $output"

#writing the response to a flat file to be FTPed to server B
`echo $output>"rp_$newCounter.txt"`
`export filename==rp_$newCounter.txt`
`echo ls -l "rp_$newCounter.txt"`
typeset -i responseSize=`wc -c rp_$newCounter.txt | cut -d" " -f1`
echo "Response size $responseSize"

#If the process response is garbled, small or null, sending a dummy error in FTP file
if [ $responseSize = 1 ];then
`echo "We are working , try later" > "rp_$newCounter.txt"`
fi

#making an FTP connection to serverB and launching the response file
`curl -s -T "rp_$newCounter.txt" -u username:password"ftp://serverB/rp_$newCounter.txt"`
echo "Uploaded the FTP file for $newCounter request"
`rm -f rp_$newCounter.txt`
echo "Deleting rp_$newCounter.txt after upload"

#Updating the request environment variable
lastCounter=$newCounter
export lastCounter
fi
else
lastCounter=`curl -s http://serverB/mobRequests.txt | tail -1 | cut -d: -f1`
export lastCounter
fi
done

The whole system works very well, and the requests are processed and response send to user. There are however limitations to this model.