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I print MBR with hexdump and I get the following output:
000001a0 67 60 6f 70 65 72 61 74 69 6e 67 60 73 79 73 74 |g`operating`syst|
000001b0 65 6d 00 40 00 63 7b da c5 f5 61 68 00 40 00 40 |em.@.c{...ah.@.@|
000001c0 00 40 00 40 00 40 00 40 00 40 00 40 00 40 00 40 |.@.@.@.@.@.@.@.@|
*
000001f0 00 40 00 40 00 40 00 40 00 40 00 40 00 40 55 ea |.@.@.@.@.@.@.@U.|
00000200
What does the astersik * mean in the output?
A line in the hexdump output consisting just a * means same as the line above. This is mentioned in the hexdump's manpage at the -v option (easy to be overlooked).
-v to avoid this, so that your parser doesn't need to take it into account.
Mar 25, 2017 at 3:05
* can mean one line of more, as many as there are until the proper offset.
Apr 6, 2020 at 13:05
hexdump shows, but what it really means is you've got a file with nothing but zeros in it.
As mentioned in the comments, without to verbose option to hexdump, -v, the asterisk indicates "same as above". Most likely seen on empty files or parts thereof:
> hexdump -C -s 12 -n 32 test-data/blk00000.dat
0000000c 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
0000002c
Adding the option -v to hexdump gives the full result, which is especially useful, if the output is used as input to some other process:
> hexdump -v -C -s 12 -n 32 test-data/blk00000.dat
0000000c 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
0000001c 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
0000002c
(Answer added for completeness)
dumpand it meanssame as above.*can mean more than one line be careful.