I have to find out the type of compression of the linux kernel of my arch linux system, but I can't find a way to get it more than the theory: now bzip2 (bz), formerly gzip (z).
In my computer I run the command:
$ file /boot/vmlinuz-linux /boot/vmlinuz-linux: Linux kernel x86 boot executable bzImage, version 5.3.11-arch1-1 (linux@archlinux) #1 SMP PREEMPT Tue, 12 Nov 2019 22:19:48 +0000, RO-rootFS, swap_dev 0x5, Normal VGA
Looking at the theory, I see that
bzImage must be compressed by
gzip (z), but I can't prove it:
The bzImage was compressed using gzip until Linux 2.6.30 which introduced more algorithms. Although there is the popular misconception that the bz prefix means that bzip2 compression is used (the bzip2 package is often distributed with tools prefixed with bz, such as bzless, bzcat, etc.), this is not the case.
Is there any way to prove it on my own machine? or is the theory itself, in this case, "empirical"?