--- a/wlcsv2c.pl
+++ b/wlcsv2c.pl
@@ -2,21 +2,21 @@
 # Rodolfo Garcia kix_at_kix.es
 # suspend database management v1.0
 
-use Switch;
+use feature qw(switch);
 
-switch ($#ARGV) {
-  case 0 {
+given ($#ARGV) {
+  when (0) {
     my $fin = $ARGV[0];
     open(INF, "<$fin") or die "Could not open input file\n";
     open(OUF, ">&STDOUT") or die "Could not open output file\n";
   }
-  case 1 {
+  when (1) {
     my $fin = $ARGV[0];
     my $fout = $ARGV[1];
     open(INF, "<$fin") or die "Could not open input file\n";
     open(OUF, ">$fout") or die "Could not open output file\n";
   }
-  else {
+  default {
     my $msg = $0 . " <input-file> [output-file]";
     die $msg;
   }