# dd
# Convert and copy a file (AKA: Destroyer of Disks)

# Read from `/dev/urandom`, 2*512 Bytes, and put it into `/tmp/test.txt`.
# Note: each iteration reads 512 bytes (the selected block size).
dd if=/dev/urandom of=/tmp/test.txt count=2 bs=512

# Watch the progress of dd(1).
dd if=/dev/zero of=/dev/null bs=4KB &
export dd_pid=`pgrep '^dd'`
while [[ -d /proc/$dd_pid ]]; do
    kill -USR1 $dd_pid && sleep 1
    clear
done

# Watch the progress of dd(1) with pv(1) and dialog(1), both of which can be
# installed with the following command: apt-get install pv dialog
(
    pv -n /dev/zero | dd of=/dev/null bs=128M conv=notrunc,noerror
) 2>&1 | dialog --gauge "Running dd command (cloning), please wait..." 10 70 0

# Watch the progress of dd(1) with pv(1) and zenity(1), both of which can be
# installed with the following command: apt-get install pv zenity
(
    pv -n /dev/zero | dd of=/dev/null bs=128M conv=notrunc,noerror
) 2>&1 | zenity --title 'Cloning with dd(1) -- please wait...' --progress

# Watch the progress of dd(1) with the built-in `progress` functionality, -
# introduced in CoreUtils v8.24.
dd if=/dev/zero of=/dev/null bs=128M status=progress

# DD with "graphical" return
dcfldd if=/dev/zero of=/dev/null bs=500K

# This will output the sound from your microphone port to the ssh target
# computer's speaker port. The sound quality is very bad, so you will hear a
# lot of hissing.
dd if=/dev/dsp | ssh -c arcfour -C username@host dd of=/dev/dsp

# Show current progress without interruption (USR1)
dd if=/dev/zero of=/dev/null & pid=$!
kill -USR1 $pid

# Create a 1GiB file with nothing but zeros, ready to mkswap(8) it.
dd if=/dev/zero of=/swapfile count=1048576 bs=1024 status=progress