another possibilty is to read the whole file in one string and match it there 
use strict;
use warnings;

#slurp mode, read whole file in one variable
$/ = undef;
my $text = <DATA>;

if ($text =~ /xxxxx.*?\n.*?yyyyy.*?\n.*?zzzzz/) {
    print "match \n";
} else {
    print "no match \n";
}

__DATA__

xxxxx bla
yyyyy bla
bla zzzzz

[download]
if you want to match only if the three lines are excatly xxxxx, yyyyy and zzzzz respectivly, remove the .*? from the regex

In reply to Re: regex on previous lines by si_lence
in thread regex on previous lines by MacScissor

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