stat is your friend

From the Perldocs..

Returns a 13-element list giving the status info for a file, either th
+e file opened via FILEHANDLE, or named by EXPR. If EXPR is omitted, i
+t stats $_. Returns a null list if the stat fails. Typically used as 
+follows:

    ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
       $atime,$mtime,$ctime,$blksize,$blocks)
           = stat($filename);

Not all fields are supported on all filesystem types. Here are the mea
+ning of the fields:

  0 dev      device number of filesystem
  1 ino      inode number
  2 mode     file mode  (type and permissions)
  3 nlink    number of (hard) links to the file
  4 uid      numeric user ID of file's owner
  5 gid      numeric group ID of file's owner
  6 rdev     the device identifier (special files only)
  7 size     total size of file, in bytes
  8 atime    last access time in seconds since the epoch
  9 mtime    last modify time in seconds since the epoch
 10 ctime    inode change time (NOT creation time!) in seconds since t
+he epoch
 11 blksize  preferred block size for file system I/O
 12 blocks   actual number of blocks allocated
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Here is a quick and dirty hack of how to do it without using dir..

#! /usr/bin/perl

use strict;
use warnings;
use File::stat;

my $dir = $ARGV[0] || "./";
my ($time1, $time2, $returnname);

opendir (DIR, $dir) or die "Cannot open $dir: $!\n";
while( my $file = readdir( DIR ) ) {
    next if $file =~ /^\./;
    my $sb = stat($file);
    $time2 = $sb->mtime;
    if ($time2 > $time1) {
        $time1 = $time2;
        $returnname = $file;
    }
   #printf "File is %s, size is %s, mtime %s\n", $file, $sb->size, $sb
+->mtime;
}

print "Newest file is $returnname\n";
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Note the mtime is returned as an epoc time so if you want yesterdays file all you have to do is subtract 86400 seconds... type stuff...

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Of all the things I've lost in my life, its my mind I miss the most.