Shell Programming and Scripting

$ grep "<BATCH_ID>" input | sed 's:<[\/]*BATCH_ID>::g''
12345678519

if (/\[<\?xml/../^\]/)
    { # Read all those lines from file between (and including) lines containing "<?xml" to "]"
    if (/\[<\?xml/)
    { # If line contains "<?xml"
        $f=0; # set a flag to zero
        s/.*?(\[<\?xml.*)/$1/; # Remove text before "<?xml" in line containing "<?xml", or rather keep text from "<?xml" till end of line
        $x=$_; # Store the edited value in $x
        print $x;
    }
    elsif (/<BATCH_ID>12345678519<\/BATCH_ID>/)
   { # Check if line contains <BATCH_ID>12345678519</BATCH_ID>
        $f=1; # Set flag to one
        print $x; print; # Print line containing "<?xml" and line containing batch id
    }
    elsif (!/\[<\?xml/ && !/<BATCH_ID>12345678519<\/BATCH_ID>/ && $f==1) { print } # If line doesnt contain "<?xml" and batch id and if flag is set to one, then print the line
    elsif ($f==0) { next } # If flag is zero while processing a line, skip it.
}' helium-core.log # Process the file 'inputfile'

elsif (!/\[<\?xml/ && !/<BATCH_ID>$BATCHID<\/BATCH_ID>/ && $f==1)

#! /usr/bin/perl -w
use strict;

( @ARGV != 1 ) && die "Enter exactly one batch_id. Exiting";
# my @ARGV = ("12345678519"); # Un-comment this line and comment above line if you don't want to give batchid as parameter and want to define in script itself.
my ($f, $x);

open XML, "< input";
for (<XML>) {
    if (/\[<\?xml/../^\]/) {
        if (/\[<\?xml/) { $f=0; s/.*?(\[<\?xml.*)/$1/; $x=$_ }  
        elsif (/<BATCH_ID>$ARGV[0]<\/BATCH_ID>/) { $f=1; print $x; print }
        elsif (!/\[<\?xml/ && !/<BATCH_ID>12345678519<\/BATCH_ID>/ && $f==1) { print }
        elsif ($f==0) { next }
    }
}

$ ./test.pl 12345678519
[<?xml version="1.0" encoding="UTF-8"?><ESP_SSIA_ACC_FEED>
<BATCH_ID>12345678519</BATCH_ID>
<UID>3498748823</UID>
<FEED_TYPE>FULL</FEED_TYPE>
<MART_NAME>SSIA_DM_TRANSACTIONS</MART_NAME>
<MART_TYPE>SSIA_TRANSACTIONS</MART_TYPE>
<CLIENT_ID>ESPDB</CLIENT_ID>
<SQL>FROM  SSIA_DM_TRANSACTIONS  WHERE   ASAT BETWEEN '2012-01-10T03:44:48.385' and '2012-01-11T03:43:46.646' AND       SSIA_ACCOUNT_CODE = 'BTAC2091' AND PORTF        OLIO_CODE = '02091' </SQL>
</ESP_SSIA_ACC_FEED>
]