[Rd] no internal function "int.unzip" in R 2.9 on Windows

[Duncan Murdoch]

On 3/25/2009 11:42 AM, audrey at ebi.ac.uk wrote:
> Dear list,
> 
> Using R 2.9, I have the following error on Windows when I try using
> .Internal(int.unzip(...)):
> 
>> .Internal(int.unzip("test.zip",NULL, "."))
> Error in .Internal(int.unzip("test.zip", NULL, ".")) :
>   no internal function "int.unzip"
> 
> The same error also happens with R 2.10 but not on R 2.8. And it does not
> happen with R 2.9 on Mac or Unix.
> I have googled the error message but cannot find much.
> 
> Does anyone know if the way R calls unzip functions on Windows has changed
> and if this is permanent?
> I am sorry if I miss something obvious, but any suggestions on how I can
> fix the problem?
> I want to keep using int.unzip and not the utils function unzip because I
> use its output afterwards in my script.

Generally internal things that aren't documented as part of the API are 
subject to change without notice.  Rather than relying on the way 
certain functions happen to work in certain versions, if you find that 
one of the documented functions doesn't do what you want, you should 
point out the problem with it and submit a patch.

You can see how the unzip function in the utils package works by looking 
at the source, or just printing it in the console.  It doesn't refer to 
int.unzip, but I wouldn't count on its current behaviour being 
"permanent":  it's undocumented internal implementation, which you use 
at your own risk.

Duncan Murdoch