#!/usr/bin/perl 
use strict; 
use warnings; 
 
my $file_number; 
my @input_files; 
 
$file_number = $#ARGV; 
if ($file_number == -1 || $file_number > 11) 
{ 
   die "Usage: timelapse.pl inputfile1.dat inputfile2.dat ... \n"; 
} 
 
# open files specified on the command line and store handles in the input_files array 
my $i; 
my @content; 
for ($i = 0; $i <= $file_number; $i++) 
{ 
   open($input_files[$i], "< $ARGV[$i]") or die "can't open datafile: $!\n"; 
   print "file $ARGV[$i] opened \n"; 
   @content[$i] = <$ARGV[$i]>; 
}

#!/usr/bin/perl  
use strict; 
use warnings; 
use Data::Dumper; 
my @input_files = @ARGV; 
verify_usage(@input_files); 
my @content; 
foreach my $file_name (@input_files) { 
    open my $FILE, '<', $file_name or 
        die "Cannot open '$file_name' for input\n"; 
    my @text = <$FILE>; 
    push @content, [@text]; 
    close $FILE; 
} 
print Dumper \@content;  
 
 
sub verify_usage { 
    my @input_files = @_; 
    my $number_of_files = @input_files; 
    if ( 
        ($number_of_files ==  0)  || 
        ($number_of_files  > 12)  || 
        grep {!/\.dat$/i}  @input_files  
    ) { 
        die "\nUsage: timelapse.pl inputfile1.dat inputfile2.dat ... \n"; 
    } 
}