Is there a regular expression in Perl to find a file's extension?

my $file = "test.exe";

# Match a dot, followed by any number of non-dots until the
# end of the line.
my ($ext) = $file =~ /(\.[^.]+)$/;

print "$ext\n";

use File::Basename

  use File::Basename;
  ($name,$path,$suffix) = fileparse("test.exe.bat",qr"\..[^.]*$");
  print $suffix;

\.[^\.]*$

This would give you everything after the last dot (including the dot itself) until the end of the string.