On 2/11/2013 6:54 PM, Pascal Hambourg wrote:
Bob Proulx a écrit :Pascal Hambourg wrote:Bob Proulx a écrit :$ perl -le 'print 5605687296 / (1024*1024*1024)'Note that 1 GB (gigabyte) is 10^9 bytes as can be seen in the GNU dd output. 1024^3 is 1 GiB (gibibyte).For me I prefer binary powers of two when using it in relation to computer tasks.This is perfectly fine. But you proposed this command to mimic the output of GNU dd, which uses SI prefixes (powers of 10).
Historically, byte counts have been based on powers of 2 - 2^10 is 1Kb, 2^20 is 1Mb, etc.
But back in the mid 80's when hard disks started coming out for PC's (all - not just IBM derivatives), companies wanted to make their drives look as big as they could. So a drive which had 81,920 512 byte sectors (41,943,040 bytes) was 41 (or even 41) mb, instead of 40mb as computer users previously defined storage. And therefore the confusion as to what actually makes up a gigabyte.
I'm with Bob. A gigabyte is still 2*30. And this laptop has 4GB of ram - which means 4,294,967,296 bytes - not 4,000,000,000 bytes.