What is the output of
date -u +%W$(uname)|sha256sum|sed 's/\W//g' (on Arch Linux if it matters)?
How do I find that out?
date -u %W
Displays the current week of the year.
Displays the kernel name.
Generates a SHA-256 Hash Sum.
Cuts out all non-word characters.
|'s are redirecting the output of the first command to the appending command.
Enter the line in a terminal, f.e.
date -u +%W$(uname)|sha256sum|sed 's/\W//g'
Depending on the date and the operating system installed, this will output different hashes, like this:
1. The 'uname' part
-s Displays the system name. This flag is on by default.
-s, the man page says "print the kernel name". On Arch Linux
whereas on, for example, Cygwin
uname returns something like:
2. 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.
3. 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)
On Cygwin it can be computed as:
echo '07Linux'|sha256sum|sed 's/\W//g'
(This actually worked when I tried to register at ArchWiki...)