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Comment by donaldihunter | Hacker News Reader

Cult of pv. It looks to have more command-line complexity than dd. https://linux.die.net/man/1/pv

This is a good point as well. On BSD, we don't have `pv`, but we do have ^T. This will print some sort of status for just about any long running process. It prints very specialized status for certain programs aware of it.

Nice! MacOS has it too (unsurprisingly)

Linux, not. I wonder why.

Huh, I never knew about this. It looks like Linux doesn't define SIGINFO, which is what the terminal driver would generate in response to the ^T.

You're not the first to wonder: https://unix.stackexchange.com/questions/179481/siginfo-on-g...

But it looks like the answer is just "it was complicated to implement so Linux didn't add it."

You made my day sir

pv is available on at least FreeBSD as a package like it is in Linux. I'd be quite shocked if the other BSD's didn't have a port of it as well. There is also mbuffer.

SIGINFO works on gnu dd last I tried it.

Yeah, it's just that Linux doesn't even define SIGINFO

pv is probably more useful:

  $ dd if=/dev/urandom count=1000 bs=1000000 | pv -s 1000000000 > foo
   214MiB 0:00:16 [13.1MiB/s] [========================>                                                                                         
  ] 22% ETA 0:00:55

Compare to ^T:

  $ dd if=/dev/urandom of=foo count=1000 bs=1000000
  load: 1.76  cmd: dd 80097 running 0.00u 0.89s
  11+0 records in
  11+0 records out
  11000000 bytes transferred in 0.947316 secs (11611752 bytes/sec)
  load: 1.76  cmd: dd 80097 running 0.00u 1.68s
  22+0 records in
  22+0 records out
  22000000 bytes transferred in 1.746013 secs (12600134 bytes/sec)
  load: 1.76  cmd: dd 80097 running 0.00u 2.28s
  31+0 records in
  31+0 records out
  31000000 bytes transferred in 2.392392 secs (12957742 bytes/sec)
  load: 1.76  cmd: dd 80097 running 0.00u 2.83s
  38+0 records in
  38+0 records out
  ....

Why not using native dd parameter status=progress ?

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