based on meego, sailfish is the first real open source mobile operating system that also runs android apps thanks to myriads alien dalvik. the Qt swipe UI allows to swipe away apps and push them to the multitasking homescreen where the app will act as interactive widget. an application drawer lives underneath the homescreen and can be accessed via swipe up. as seen in meego, the lock screen shows notifications and allows quick-access to the camera, phone, profiles and more with a swipe down. swiping away an app half way allows a glance at the homescreen and whats going on there without leaving the app.
jolla plans to launch the first sailfish phones in the second quarter of 2013.
“dd” is the command to make a bit-by-bit copy of “if=/dev/sda” as the “Input File” to “of=sda.img.gz” as the “Output File”. Everything from the partition will go into an “Output File” named “sda.img.gz”. “conv=sync,noerror” tells dd that if it can’t read a block due to a read error, then it should at least write something to its output of the correct length. Even if your hard disk exhibits no errors, remember that dd will read every single block, including any blocks which the OS avoids using because it has marked them as bad. “bs=64K” is the block size of 64×1024 Bytes. Using this large of block size speeds up the copying process. The output of dd is then piped through gzip to compress it.
Store extra information about the drive geometry necessary in order to interpret the partition table stored within the image. The most important of which is the cylinder size.
# fdisk -l /dev/hda > sda_fdisk.info
backup just one partition
# dd if=/dev/sda2 of=sda2.img
One of the disadvantages of the dd method over software specifically designed for the job such as clonezilla is that dd will store the entire partition, including blocks not currently used to store files, whereas the likes of clonezilla understand the filesystem and don’t store these unallocated blocks. The overhead isn’t too bad as long as you compress the image and the unallocated blocks have low entropy. In general this will not be the case because the emtpy blocks contain random junk from deleted files. To rectify this, it’s best to blank all unused blocks before making the image. After doing that, the unallocated blocks will contain mostly zeros and will therefore compress down to almost nothing.
Mount the partition, then create a file of zeros which fills the entire disk, then delete it again.