+open DEBUG, ">/dev/null" or die $!;
+
+sub debug {
+ print DEBUG "$us: DEBUG: ", @_, "\n" or die $!;
+}
+
+sub debug_cmd {
+ debug "running ", join ' ',
+ map {
+ if (m/[^-_.=+0-9a-z]/i) {
+ my $s = $_;
+ $s =~ s/['\\]/'\\$&'/g;
+ "'$s'";
+ } else {
+ $_;
+ }
+ } @_;
+}
+