Thank you very much haukex!

The API of XML::Writer appeared to be a bit too complex for me at first. However I tried it just now - and indeed it seems to write the output continually (which I checked with the commented "Hi" line below. The syntax was not very verbose either on the second look :-) A bit strange (to my taste) is the option NEWLINES which adds a newline before the closing delimiter, however it does make the output human readable.

I will test the module with my real data. Many thanks again!

#!/perl
use strict;
use warnings FATAL => qw(all);

use Text::CSV_XS;
use XML::Writer;

my $csv_par =  { binary => 1, auto_diag => 1, 
     allow_whitespace => 1, sep_char => ';', 
     eol => $/, quote_char => undef, };

my $csv = Text::CSV_XS->new($csv_par);
my @header = @{$csv->getline(*DATA)};

my %rec;
$csv->bind_columns(\@rec{@header});

my $writer = XML::Writer->new(NEWLINES => 1,
          ENCODING => 'UTF-8'); # stdout.
$writer->xmlDecl(); # ("UTF-8") already mentioned above.
$writer->startTag('ROOT');

while ( $csv->getline(*DATA) )
{
     $writer->startTag('alpha', 'name' => $rec{"alpha"});
     for my $other( qw(beta gamma) )
     {
          $writer->startTag($other, 'name' => $rec{$other});
          $writer->endTag($other);
     }
     # print "\t\tHi!\n";
     $writer->endTag('alpha');
}
$writer->endTag('ROOT');
$writer->end();

__DATA__
alpha;beta;gamma
q;2;3
w;9;8
e;1;2
r;6;7
t;5;9
y;3;1
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