#!/usr/bin/perl -w
use strict;

# this is just so that glob() whitespace handling is sane
use File::Glob qw(bsd_glob);

my $fname = "empty";

my @found_files;
while (! @found_files){
       print "Please enter Filename: ";
       chomp($fname = <STDIN>);

       @found_files = glob( "/Users/johnsmith/data/$fname*" );
       if (@found_files != 1) {
           if (@found_files == 0) {
               print "File '/Users/johnsmith/data/$fname*' does not exist.\n\n";
           } else {
               print "There are multiple files matching '/Users/johnsmith/data/$fname*':\n";
               print "$_\n" for @found_files;
           };
       };
}
print "I have found this '$found_files[0]' in your directory\n\n";