Then read man systat and find the section about display iostat, it has a
command:

split       Toggle the display of separate read/write statis-
             tics (the default is combined statistics).


Federico Giannici wrote:
quoted text
> Tom Van Looy wrote:
>> $ systat -w 1 iostat
>
> Unfortunately under 3.9 (where I need it) the output is different and
> reads and writes are not separate.
>
> Anything similar working under 3.9?
>
> Thanks.
>
>
>> Federico Giannici wrote:
>>> I'd like to know how much of the disk activity is for reads and how
>>> much is for writes.
>>>
>>> It seems that there are a few system commands that show statistics
>>> about disks activity (iostat, vmstat, systat) but none of them
>>> separate reads and writes.
>>>
>>> Is there some command that shows the READ disk stats and WRITE disk
>>> stats, SEPARATELY?
>>>
>>>
>>> Thanks.