On 28 May 2017 at 21:58, Richard Owlett <rowl...@cloud85.net> wrote: > It says in part: >> >> Sending a USR1 signal to a running 'dd' process makes it print I/O >> statistics to standard error and then resume copying. >> >> $ dd if=/dev/zero of=/dev/null& pid=$! >> >> $ kill -USR1 $pid; sleep 1; kill $pid > > > I think it is trying to tell me what I need to know. > But there is too much going on there, > Guidance please.
If you browse to explainshell.com and paste shell commands that you don't understand, it parses the commands and gives excerpts from relevant docs, which might help you in future. I pasted your two command above, and received the following results. (If perhaps these links dont work, just paste the commands yourself). https://explainshell.com/explain?cmd=dd+if%3D%2Fdev%2Fzero+of%3D%2Fdev%2Fnull%26+pid%3D%24! https://explainshell.com/explain?cmd=kill+-USR1+%24pid%3B+sleep+1%3B+kill+%24pid
