Even if you can't directly do an FTP put from the <DATA> filehandle, you can write <DATA> to a real file, then put that file.

# Completely untested :(
use Net::FTP;
use File::Temp qw(tempfile);
my ($fh, $filename) = tempfile( DIR => '/' );
print $fh <DATA>;
close $fh;
... set up your $ftp connection ...
$ftp->put($filename);
$ftp->quit;
unlink $filename;
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