Links: TECHNOLOGY - PROGRAMMING
Rel: macos; linux; commands
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Tags: #public

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dd = heavy-lifting, bit-by-bit copy

if="input file"(source)
of="output file"(destination)

dd if=/dev/sda of=/dev/sdb

dd if=/dev/sda2 of=~/backup.img # to backup or bootable media {: id="to-backup-or-bootable-media" }

dd if=/dev/zero of=/dev/sdb # copies from a preset bunch of zeros; used to wipe the destination partition  {: id="copies-from-a-preset-bunch-of-zeros;-used-to-wipe-the-destination-partition" }

sudo dd if=/dev/zero of=/dev/sdX bs=1M status=progress
sudo dd if=/dev/urandom of=/dev/sdX count=7 status=progress

see also: fdisk