Some readers will have another issue and need this fix. read the links below. the same problem occured with visual studio 2015 with the advent of windows sdk 10 which brings up libucrt. ucrt is the windows implementation of C Runtime (CRT) aka the posix runtime library. You most likely have code that was ported from unix... Welcome to the drawback
https://github.com/lordmulder/libsndfile-MSVC/blob/master/src/sf_unistd.h
https://lists.gnu.org/archive/html/bug-gnulib/2011-09/msg00224.html
https://msdn.microsoft.com/en-us/library/y23kc048.aspx
https://blogs.msdn.microsoft.com/vcblog/2015/03/03/introducing-the-universal-crt/