Portability problems fixed by Gnulib:
@itemize
+@item
+This function is missing on some platforms:
+Solaris 2.4, mingw, BeOS.
@end itemize
Portability problems not fixed by Gnulib:
@itemize
@item
-This function is missing on some platforms:
-Solaris 2.4, mingw, BeOS.
+On platforms that do not natively support this function,
+it has unspecified behavior in a multi-threaded process.
@end itemize