View Full Version : [ubuntu] commands: date, sed together ?

July 17th, 2011, 09:28 AM

Can anyone tell me, what this returns and explain it a bit :)

date -u +%W$(uname)|sha256sum|sed 's/\W//g˝˝

July 17th, 2011, 09:55 AM
Surely that should be

date -u +%W$(uname)|sha256sum|sed 's/\W//g'

It calculates a sha sum of the date and the word Linux, then sed is used to only print the actual sum.

If you want to see it work, just run it step by step:

date -u +%W
date -u +%W$(uname)
date -u +%W$(uname)|sha256sum
date -u +%W$(uname)|sha256sum|sed 's/\W//g'

You could also use cut rather than sed:

date -u +%W$(uname) | sha256sum | cut -d' ' -f1