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Re: Some help with dd backing up into an iso




David Christensen [2017-03-06 21:05:31-08] wrote:

>     # dd if=/dev/sda | gzip > myimage.img

What's the point of using dd?

    gzip </dev/sda >myimage.img

I don't know about you but many people seem to think that dd is some
kind of special tool for reading and writing block device files. But
after all the devices are just files that can be read with normal
commands like cat or cp. These are even faster normally because they use
larger buffers. Write operations on device files should be finished with
sync command to flush the buffers.

To copy a device file:

    cat /dev/foo >image.img

To write to a device:

    cp image.img /dev/foo
    sync

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