Perl module File::Slurp

use warnings;
use strict;

use File::Slurp;

#
#  Read file into string (scalar context).
#
my $file_text=read_file(__FILE__); 
print $file_text;

#
#  Read file into array (list context).
#
my @file_lines=read_file(__FILE__); 
print join ". ", @file_lines;

#
#  Write a file (write this script in uppercase letters)
#
write_file('file.out', map { uc } @file_lines);

use warnings;
use strict;

use File::Slurp;

my $file_name = 'written_file.txt';

unlink $file_name if -f $file_name;

my @lines = (
  "foo bar baz\n",
  "one two three\n",
  "1 2 3 4 5 6 7 8 9\n"
);

write_file($file_name, @lines);