If you really need a line-based approach rather than just loading the whole thing into memory (most of the time, the latter approach will work just fine), then you need to cache the previous lines and do a search of the cache: 
use strict;
use warnings;

my $csize = 2;   ### Number of lines to save
my (@cache, $str, $c);

my $file = 'data.txt';

open (IN, $file) or die "Can't open $file for read.";
while (<IN>) {
    shift @cache if $#cache == $csize - 1;
    push @cache, $_;
    $c++;

    $str = join '', @cache;
    if ($str =~ /jumped\nover/) {
        print "String found in $file at lines " . ($c - $#cache) . "-$
+c:\n";
        print $str;
        last;
    }
}

[download]
Input file data.txt: 
the
quick
brown
fox
jumped
over
the
unfortunate
dog

[download]
Output: 
String found in data.txt at lines 5-6:
jumped
over

[download]

In reply to Re: how to read multiple line from a file by TJPride
in thread how to read multiple line from a file by skyworld_chen

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