If you always have your zone definitions separated with blank lines, but no blank lines in the zone blocks, the task is even easier - read and write the file in paragraph mode: 
#!/usr/bin/perl -w -ni.bak -00

use strict;

BEGIN {
    local $/ = "\n";
    print "please enter the domain name: ";
    use vars qw($targetdomain);
    chomp ($targetdomain = <STDIN>);
}

print unless /^zone\s+"$targetdomain"/;

[download]
Call that script with the zone file as argument, e.g. 
perl zonedel.pl /home/blackice/hello

[download]

It will create a backup of the file. For the switches after '#!/usr/bin/perl' see perlrun.

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re^11: Deleting lines from named.conf file by shmem
in thread Deleting lines from named.conf file by firewall00

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