Hi ccherri,

You can use XML::Simple to do modifications too: 

use XML::Simple;
my $inst_set = XMLin( 'test.xml', KeepRoot => 1 );

foreach my $Channel (@{$inst_set->{Settings}->{Channels}->{Channel}}) 
+{
  if ( $Channel->{Voltage} ) {
    print "Old voltage: $Channel->{Voltage} -- ";
    $Channel->{Voltage} *= 2.0;
    print "New voltage: $Channel->{Voltage}\n";
  }
}
my $xml = XMLout( $inst_set, KeepRoot => 1 );

print $xml;

[download]
Update:'KeepRoot' was added in according to AM's comments below.

In reply to Re: confirming key in xml? by pme
in thread confirming key in xml? by ccherri

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