But the replacement function is not safe to be used in libraries and is not multithread-safe.
@item
Some systems mistakenly succeed on @code{unlinkat(fd,"file/",flag)}:
-Solaris 9.
+GNU/Hurd, Solaris 9.
+@item
+Some platforms declare this function in @code{fcntl.h} instead of
+@code{unistd.h}:
+Cygwin 1.7.1.
@end itemize
Portability problems not fixed by Gnulib: