+sub download_cmd($) {
+ my $url = shift;
+ my $have_curl = 0;
+
+ if (open CURL, '-|', 'curl', '--version') {
+ if (defined(my $line = readline CURL)) {
+ $have_curl = 1 if $line =~ /^curl /;
+ }
+ close CURL;
+ }
+
+ return $have_curl
+ ? (qw(curl -f --connect-timeout 20 --retry 5 --location --insecure), shellwords($ENV{CURL_OPTIONS} || ''), $url)
+ : (qw(wget --tries=5 --timeout=20 --no-check-certificate --output-document=-), shellwords($ENV{WGET_OPTIONS} || ''), $url)
+ ;
+}
+