Hi, Richard Owlett wrote: > Am I correct that there is a problem with the man page?
Not with that example. It works as to be expected from the description. The example in the coreutils manual gives a better motivation why one would want to send USR1 signals to the running dd process. > The [example] script copies bytes until the second line is encountered. > It outputs data and *STOPS DEAD* That's because the second kill command sent the default signal TERM, which other than USR1 causes dd to end. Without the final kill $pid the dd process would run in background until you shut down your computer. If you send more USR1 by kill -USR1 $pid before the TERM signal then you get more output lines with increasing byte counts: 106330856+0 records in 106330856+0 records out 54441398272 bytes (54 GB) copied, 21.859 s, 2.5 GB/s 113139254+0 records in 113139254+0 records out 57927298048 bytes (58 GB) copied, 23.2586 s, 2.5 GB/s 121925708+0 records in 121925707+0 records out 62425961984 bytes (62 GB) copied, 25.0622 s, 2.5 GB/s That you get richard@stretch-2nd:~$ from the kill command line does not actually mean that the dd process has ended (although it has in this special case). This is because of the ampersand at the end of the dd command. But the next shell command line after the end of the dd process should report its demise before the commands in that line get executed: [1]+ Terminated dd if=/dev/zero of=/dev/null Further you may check by ps -ef | fgrep 'dd if=/dev/zero' whether the process is still running. If so, you will see an output line like thomas 12084 1716 99 17:06 pts/8 00:00:03 dd if=/dev/zero of=/dev/null where 12084 is the process id number of the dd run. Have a nice day :) Thomas
