@itemize
@item
This function is missing on some platforms:
-OpenBSD 3.8, HP-UX 11, IRIX 6.5, OSF/1 4.0, Solaris 7, Cygwin 1.5.x, mingw, Interix 3.5, BeOS.
+OpenBSD 3.8, HP-UX 11.23, IRIX 6.5, OSF/1 4.0, Solaris 7, Cygwin 1.5.x,
+mingw, Interix 3.5, BeOS.
+
+@item
+This is available only as a macro, rather than a function, on some
+platforms:
+OpenBSD 4.6, MirBSD 10.
@end itemize