[Rd] typo in docs for unlink()

[Tony Plate]

The VALUE section in the help for 'unlink' says:

|  0| for success, |1| for failure. Not deleting a non-existent file is 
not a failure, nor is being unable to delete a directory if |recursive = 
FALSE|. However, missing values in |x| result are regarded as failures.

The last phrase doesn't make sense to me.  Should it be either "missing 
values in x are regarded as failures" or "missing values in x result in 
failure" ?

Also, after reading the docs, I'm still unable to work out if unlink() 
will return 1 when the user tries to recursively delete a directory on 
systems that don't support recursive=T.

The DETAILS section says "recursive=TRUE is not supported on all 
platforms, and may be ignored, with a warning", which could be 
interpreted as implying no special action when recursive=TRUE is not 
implemented (other than a warning()), and the VALUE section doesn't say 
what the return value will be under such conditions.

I've skimmed the various *_unlink functions in src/main/platform.c, and 
it looks like they all implement recursive=TRUE, so I'm still in the 
dark about the required behavior on systems that don't support it.  
Could this be clarified in the help file?

thanks,

Tony Plate