I'm not quite sure if the code below is what you're looking for, but it works for what it seems that you want to do:

#!/usr/bin/perl
use strict;
use warnings;

print "Please enter text for string search: ";
my $search=<STDIN>;
chomp $search;

opendir(DIR, ".") or die "Cannot open dir ($!)\n";

while (my $file = readdir(DIR)) {
    print "$file\n" if ( $file =~ /$search\.jpg|$search\.jpeg/i );
}
closedir(DIR);
exit 0;
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As others have said, it's a good idea to use warnings and use strict, always. This would be easy to modify to make it accept input on the directory as well. The i flag at the end of the regex ( /pattern/i ) makes it match case-insensitive. That way you do not need to specify JPEG, Jpeg, jpeg, and so on...