my @output_data_files = qw( filename1 filename2 more_filenames... );
my $pattern = qr/result/; # a regular expression that will find "result"

my @results_found;        # here goes everything that was found.

foreach my $file ( @output_data_files ) {
    open ( FILE, "< $file" )
      or die qq(could not open file "$file" for reading: $!);

    while ( <FILE> ) {    # on every line of the file
        if ( my @matches = m/$pattern/g ) { # matches of the pattern
            push @results_found, @matches;  # add them to @results_found
        }
    }
    close FILE;
}