- The 'uname' part
To answer the first question, the crucial thing is what uname without a parameter returns on Arch Linux. The man page does not define it, but uname Command says it is equivalent to uname -s:
-s Displays the system name. This flag is on by default.
For -s, the man page saysays "print the kernel name". On Arch Linux uname returns
Linux
whereas on, for example, Cygwin uname returns something like:
CYGWIN_NT-5.2-WOW64
- The 'date' part
date -u +%W returns the week number. As the last part ("Linux") is a fixed string, the final output depends on which week the command line is run in (the hash is computed on for example "07Linux"). With this knowledge the output can also be computed on Cygwin.
- An example
The week number for 2012-02-18 is 7 and date -u +%W`uname` returns (has a leading zero, but this is expected for the task at hand)
07Linux
and the output from sha256sum (a SHA-2 hash) is:
4a65f65b40cc2b0a7aaa726e895d72425ede255021e2ce3e935dd2719e4d33b9
On Cygwin it can be computed as:
echo '07Linux'|sha256sum|sed 's/\W//g'
(This actually worked when I tried to register at ArchWiki...)