Write+move instead of rewrite for dnsseed.dat
Write+move instead of rewrite for dnsseed.dat

MineChuteDev/BitcoinTX-dnsseeder,MineChuteDev/BitcoinTX-dnsseeder,MineChuteDev/BitcoinTX-dnsseeder,MineChuteDev/BitcoinTX-dnsseeder