my $dir = 'input_files';

opendir(DIR, $dir) or die "can't opendir $!";
while (defined(my $file = readdir(DIR))) {     # do something with "$dirname/$file" 
  print "The directory and file are $dir/$file\n";
  open (IN, "< $dir/$file"  ) or die ("Can't open input file $!");

  while ( < IN > ){
    print ;
  }
}
closedir(DIR);


##</code><code>##

allergies
immunizations

##</code><code>##

# Input file for allergies
# Date, Diagnosed By, Type, allergy, reaction,specifics<br>
2009-05-16,Children's Hospital Boston,drugs,penicillin,Blue rash,This only happens on weekends<br>
2009-05-17,Boston Medical Group,drugs,Vitamin B,Rash on torso,This happens after 9PM<br>
2009-05-17,Memorial Hospital,food,Diary,Upset stomach and gas, Happens after drinking whole milk<br>

##</code><code>##

perl create_indivo_schemas.pl
Name "main::IN" used only once: possible typo at create_indivo_schemas.pl line 18.
The directory and file are input_files/allergies
INThe directory and file are input_files/immunizations
INThe directory and file are input_files/..
INThe directory and file are input_files/.

##</code><code>##

open (my $fh, "< $dir/$file"  ) or die ("Can't open input file $!");

  while ( < $fh > ){
    print ;
  }

##</code><code>##

open (my $fh, "< input_files/immunizations"  ) or die ("Can't open input file $!");

##</code><code>##

my @file_list = `ls input_files`;   # get the list of files from the input directory

foreach (@file_list){  # loop through the files that are in the directory
  chomp;
  my $filename = 'input_files/'.$_;

  print "file name is : $filename\n";
  open (my $fh, "< $filename"  ) or die ("Can't open input file $!");

  open (my $fh, "< $filename"  ) or die ("Can't open input file $!");

  while ( < $fh > ){      # look through the data in the file
    print;
    print "\n";

  }