use strict;
use warnings;

sub sep { print q{=} x 50, qq{\n}; }
sep();

my $dataOffset = tell DATA;

my $printIt = 0;
while( <DATA> )
{
    if( m{begin} )
    {
        $printIt = 1;
        next;
    }
    elsif( m{^end process$} )
    {
        $printIt = 0;
        next;
    }
    else
    {
        print if $printIt;
    }
}
sep();

seek DATA, $dataOffset, 0;
$printIt = 0;
while( <DATA> )
{
    if( m{^begin} )
    {
        $printIt = 1;
        next;
    }
    elsif( m{^end process$} )
    {
        $printIt = 0;
        next;
    }
    else
    {
        print if $printIt;
    }
}
sep();

seek DATA, $dataOffset, 0;
$printIt = 0;
while( <DATA> )
{
    if( m{^begin$} )
    {
        $printIt = 1;
        next;
    }
    elsif( m{^end process$} )
    {
        $printIt = 0;
        next;
    }
    else
    {
        print if $printIt;
    }
}
sep();

__END__
hfkjd
process jhk
do not begin here
because we do not want this line
or this
start
begin
*** This is a line we want ***
*** So is this ***
end process
scrap
begin the beguine
hkl
process khfk
shoot
hooter
begin
*** Another desired piece of data ***
end process
more dross

##</code><code>##

==================================================
because we do not want this line
or this
start
*** This is a line we want ***
*** So is this ***
hkl
process khfk
shoot
hooter
*** Another desired piece of data ***
==================================================
*** This is a line we want ***
*** So is this ***
hkl
process khfk
shoot
hooter
*** Another desired piece of data ***
==================================================
*** This is a line we want ***
*** So is this ***
*** Another desired piece of data ***
==================================================