RFR: 8196882: VS2017 Hotspot Defined vsnprintf Function Causes C2084 Already Defined Compilation Error

[Kim Barrett]

> On Feb 25, 2018, at 5:37 PM, Kim Barrett <kim.barrett at oracle.com> wrote:
> Based on discussion, I've changed the new os::vsnprintf and
> os::snprintf to conform to C99.  […]
> 
> Also changed jio_vsnprintf to use os::vsnprintf, reverting some of the
> ealier change.

Just to be clear, the jio_vsnprintf behavior has not been changed.  It’s just been
reimplemented in terms of os::vsnprintf rather than directly using ::vsnprintf and
trying to account for its platform variations.