It ensures the restored output (in a regular file) will be at least as large as the filesystem being restored from the source image file. Without this option, the output file would only extend to the end of the final used block in the filesystem. That would cause problems when mounting the filesystem in the file via a loop device.
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What does this option do exactly?
create special raw file for loop device is mentioned in man page. Does it create or mount a loop device aswel as an image?
I can find very little information about it.
Thank you
Brendan
It ensures the restored output (in a regular file) will be at least as large as the filesystem being restored from the source image file. Without this option, the output file would only extend to the end of the final used block in the filesystem. That would cause problems when mounting the filesystem in the file via a loop device.