Reading something between two tags, such as <TAG>my stuff</TAG>:

my @array;
while ( my $line = <FILE> ) {
  if ( $line =~ /\<TAG\>(.*)\<\/TAG\>/ ) {
    push @array, $1;
  }
}
[download]

Putting the text of the next line into a variable after matching something on the previous line..., as in

<TAG>data</TAG>
this is data to be stored
[download]

my @array;
while( my $line = <FILE> ) {
  if ( $line =~ /\<TAG\>data\<\/TAG\>/i ) {
    my $data_line = <FILE>;
    push @array, $data_line;
  }
}
[download]

If neither case is what you want or helps you get you want to need, you need to be more specific about your format.

Okay, here's my best guess at your problem.

while (<FILE>){
    $line = /<begin>/ .. /<end>/;
    # do something powerful with $line here
}
[download]

Actually, it's a FAQ question.

Update: Included the <begin/end> tags to reflect the question.

Well, you question as written makes very little sense, but I'm wondering if you want something like this:

open FILE, 'myfile.txt' or die "Urgh: $!\n";

while (<FILE>) {
  if (/START TEXT/ .. /END TEXT/) {
    # Do something with the text in $_
    # This will be one line from the file
    # after the line containing 'START TEXT'
    # but before the line containing 'END TEXT'
  }
}
[download]

"Perl makes the fun jobs fun
and the boring jobs bearable" - me