I have a 1.0 GB .zip file on my computer which contains one file, a disk image of raspbian. When uncompressed, this file is 3.2 GB large and named 2015-11-21-raspbian-jessie.img.
After having downloaded the zip file, I have just under 1.0 GB of storage space on my computer, not enough space to extract the image to my computer.
This file needs to be uncompressed and written to an SD card using plain old dd.
Is it possible for me to write the image to the SD card under these restrictions?
I know it's possible to pipe data through tar and then pipe that data elsewhere, however, will this still work for the zip file format, or does the entire archive need to be uncompressed before any files are accessible?
I typically use unzip -p 2015-11-21-raspbian-jessie.zip >/dev/sdb or zcat 2015-11-21-raspbian-jessie.gz >/dev/sdb for convenience. This is because when doing large data transfer, we expect the operating system to automatically adjust block size (according to source block size, target block size, memory availability, etc.) for optimal performance, and it turns out they work faster than dd if= of= bs= (maybe because I did not by-brute-force try out all possible choices of blocksizes for dd) ^_^
/dev/sdh, then run
unzip -p file.zip >/dev/sdh. (I know that the use of
ddis traditional but it is not necessary.)
dd? I figured the Block Size parameter would be needed.
dd. In the past, block size was very important when writing to tapes. For disks, it doesn't matter.
ddcan only lose data or slow things down (or in rare case speed things up a little, if large enough). Forget about
dd, it's very rarely useful.