foreach my $file (@filelist) {
    if ( int( -M $file ) < 1 ) {
        # do something with a file
    }
}

##</code><code>##

#!/usr/bin/perl -w
use strict;
use File::Find;

my $directory = "d:/usr";

print "List of files newer than yesterday in $directory:\n";

find(\&process, $directory);
sub process {
    if ((int(-M) < 1) && (-f)) {
        print "  $File::Find::name\n";
    }
}

##</code><code>##

List of files newer than yesterday in d:/usr:
  d:/usr/newfile1.txt
  d:/usr/newfile2.txt