Brother haukex has already replied, but here's my answer, which more or less does the same thing:

#!perl

use strict;
use warnings;

{
    #  Disable the line ending magic, and slurp the entire string into
    #  a scalar.

    undef $/; 
    my $data = <DATA>;

    #  If we see some text between 'Test:' and 'Test2:' while looking
    #  at a multi-line string, display the resulting capture.

    if ( $data =~ /Test:(.+)Test2:/s ) { 

      print "Found |$1| between titles.\n"
    }   
}

__DATA__
Test:
Blah blah blah 1
Blah blah blah 2
Blah blah blah 5
Blah blah blah 9
Test2:
What is this for?
How is this happning?
Why am I here?
Hello3:
What
[download]

The $/ variable is the one that tells Perl what the 'end of line' character is. When I undef that variable, the whole file gets treated as a single line from an input point of view when I read the text into that variable.

The 's' option defines the regexp as a multi-line regexp, telling it to ignore the carriage return (\r) and line feed (\n) characters. When this script is run, I get

Found |
Blah blah blah 1
Blah blah blah 2
Blah blah blah 5
Blah blah blah 9
| between titles.
[download]

That's one way of parsing the file -- another way would be to

• Read lines until you see the start of the capture (Test:, in this case), then start capturing;
• Did we see the end of the capture (Test2:, in this case)? If not, capture the line and repeat; otherwise, stop.

You could also just capture each block of text into an array, store that array as a hash value, using the label (like Test) as the hash key. Later, just go and get the entry for whichever key you want.