4
votes
0answers
62 views

How come zipping a created disk image, makes smaller files than piping?

Case 1. I use dd to create an image: dd if=/dev/rdiskx of=/path/to/image bs=1m. It's 16 GB in size. I zip it, and it's suddenly around 100 MB. Case 2. I use dd to create an image, piping it ...
15
votes
5answers
446 views

Is it possible to make zcat output text even if it's uncompressed? [duplicate]

The problem is I have some database dumps which are either compressed or in plain text. There is no difference in file extension etc. Using zcat on uncompressed files produces an error instead of the ...
6
votes
2answers
6k views

gzip - redirection or piping?

I will be backing up a large (750GB) disk to an external USB disk using dd. Should I be using redirection or piping? Which is more efficient? Or is there a difference? Also, what is the best block ...