[R] save-d file format forward compatibility

[Duncan Murdoch]

Godfrey van der Linden wrote:
> G'day, All.
>
> I've recently started writing up my dissertation and need to consider how to store the research results. I'd like to use the binary compressed save() format as it is considerably smaller than the raw data.  However, will a future R be able to read it into the indefinite future or would I be better off just compressing the text data files? The doc says:
>
>   
>>      All R platforms use the XDR (bigendian) representation of C ints
>>      and doubles in binary save-d files, and these are portable across
>>      all R platforms. (ASCII saves used to be useful for moving data
>>      between platforms but are now mainly of historical interest.)
>>     
>
> The format is well known and platform agnostic, both excellent properties, but will I be able to read the data into a more modern version of R into the foreseeable future?
>
>   

Yes, that's the intention.  It can sometimes go wrong:  e.g. if you have 
an S4 object you'll likely need to have a compatible version of the 
package installed when you load the object again.  But for simple data 
types there will be no problem.

Duncan Murdoch