split takes a regex, thus this is fairly easy.

@info = split /\n(?!\[)/, $filecontents;
[download]

Thanks guys...... I've gone with brats solution.... it does the trick nicely! cheers! :)

my @what_i_want = $what_i_have =~ /(\S.*?INTERFACENAME)/gs;
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So, the places below where there is a "push", the route record is "complete" meaning there is now a single string routing record.

What you want to do past that is unclear to me. Perhaps you could explain further what info you want to extract now that you can get these records into single string entries.

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

my @routes;
my $temp='';

while(<DATA>)
{    
   next if /^\s*$/;  #skip blank lines
   chomp;
   
   if (/directly connected/)
   {
      push @routes, $_;
      next;
   }
   
   if (/via/)
   {
      push @routes, "$temp$_";
      $temp='';
      next;
   }

   $temp .= $_;

}

print join("\n",@routes),"\n";


__DATA__
C AAA.BBB.CCC.DDD 255.255.255.224 is directly connected, INTERFACENAME
O E1 WWW.XXX.YYY.ZZZ 255.255.224.0 
110/112 via AAA.BBB.DDD.EEE, 696:56:46, INTERFACENAME
[download]

/me is with hbm on "INTERFACENAME." The logic of the question, it seems to me, requires that "INTERFACENAME" be OP's standin for variable text. And on that interpretation, bart's answer is elegant after one coerces the data into a single string. ++

So, TIMTOWTDI. I've assumed variable text (and that the variable text ends with an uppercase alpha, [A-Z] character).

#!/usr/bin/perl
use Modern::Perl;

# 938143

my $cachedline="";
my $multiline="";
my (@data, $line, @array_of_routeinfo);
my $re = qr/directly connected, /;

while ( <DATA> ) {                            # slurp __DATA__
   push @data,$_ ;
}

for $line(@data) {
    chomp $line;
    $line =~ s/ $//g;      # clean up data; one of mine had trailing s
+paces
    if ($line eq '') {
        say "No more data";
        exit(1);
    }

    if ( ($line =~ /$re/ && $cachedline eq "") ) {
        push @array_of_routeinfo, $line;

    } elsif ( ($line !~ /$re/) && ($line =~ /\d$/) ) {   # if $line do
+esn't contain "directly connected, " and ends with number
        $cachedline= $line;

    } elsif ( ($line !~ /re/ && $cachedline ne "") ) {  # no "directly
+ connected, " AND $cachedline has content
        $multiline = "\t $cachedline";
        $multiline .= "\n\t $line";
        push @array_of_routeinfo, $multiline;
        $cachedline = "";
    }
}

for (@array_of_routeinfo) {
    say;
}
say "Done";

__DATA__
C AAA.BBB.CCC.DDD 255.255.255.224 is directly connected, FOO
O E1 WWW.XXX.YYY.ZZZ 255.255.224.0
[110/112] via AAA.BBB.DDD.EEE, 696:56:46, BAR
B 111.222.333.444 255.255.255.0 
[914/212] via 111.222.333.444, 345:59:03, BAZ
X EEE.FFF.GGG.HHH 255.255.255.123 is directly connected, BAT
3 L1 OOO.PPP.QQQ.RRR 255.255.111.77 
[A10/304/0xDFEE] via 444.333.222.000, 504:27:88, BLIVITZ
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Output is:

C AAA.BBB.CCC.DDD 255.255.255.224 is directly connected, FOO
         O E1 WWW.XXX.YYY.ZZZ 255.255.224.0
         [110/112] via AAA.BBB.DDD.EEE, 696:56:46, BAR
         B 111.222.333.444 255.255.255.0
         [914/212] via 111.222.333.444, 345:59:03, BAZ
X EEE.FFF.GGG.HHH 255.255.255.123 is directly connected, BAT
         3 L1 OOO.PPP.QQQ.RRR 255.255.111.77
         [A10/304/0xDFEE] via 444.333.222.000, 504:27:88, BLIVITZ
Done
[download]

I'm going to guess that 'INTERFACENAME' isn't actually static text... So maybe bart's solution, if it holds across all your data.