At the time I want to repartition a disk connected to USB, I destroyed by inattention my system disk one. Testdisk save my life.
The killing error :
cfdisk /dev/sda => modification => write.
well, as it should never be the case before changing partitions. I didn’t saved my partitions before !! :)
Include forecd option that save incrementally the partition table in (c)fdisk sould be nice, this only take few octets and could save lot of datas.