grep and glob are often very useful, for example:

my $dir = '.';
my $match = 'perl';

my @files = grep { -f } glob ( "$dir/*" );
for my $file(@files) {
    open my $fh, $file or next;
    print "Found match in $file\n" if grep{ /\Q$match\E/ }<$fh>;
}
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