Re: dd (coreutils) 5.97 used power of 10 not 2 for calculating MB

[Paul Eggert]

"Dat Head" <address@hidden> writes:

> dd if=/dev/zero of=/dev/null count=100 bs=1024k
> 100+0 records in
> 100+0 records out
> 104857600 bytes (105 MB) copied, 0.00933139 seconds, 11.2 GB/s
> ---------------------------^^^ should be 100 MB

No, "MB" means megabytes (i.e., 10**6 bytes).  I guess you want
mebibytes (i.e., 2**20 bytes), but the standard abbreviation for that
is "MiB", not "MB".  See <http://physics.nist.gov/cuu/Units/binary.html>.

It might be reasonable to add support for binary multiples to "dd",
but for media the decimal numbers are probably more useful.  As you
mentioned, most media are measured in decimal multiples nowadays.

My favorite was the old "1.44 MB" floppy, which contained 1.44 * 1024
* 1000 bytes.  Almost anything is better than that sort of confusion!