open (READER, "$file") or die "Can't read: $!\n"; 
my $req = HTTP::Request->new('PUT', "$url", undef, \&read_file_in_chunks(\*READER));


sub read_file_in_chunks {
     my ($fh_ref) = @_;
     my $content;
     read ($fh_ref, $content, 51200);
     return $content;
}