-The function @code{getopt_long_only} is missing on some platforms:
-MacOS X 10.3, FreeBSD 5.2.1, NetBSD 3.0, AIX 5.1, HP-UX 11, IRIX 6.5, OSF/1 5.1, Solaris 9, mingw, Interix 3.5.
+The glibc implementation allows a complete reset of the environment,
+including re-checking for @env{POSIXLY_CORRECT}, by setting
+@code{optind} to 0. Several BSD implementations provide @code{optreset},
+causing a reset by setting it non-zero, although it does not
+necessarily re-read @env{POSIXLY_CORRECT}. Solaris @code{getopt} does
+not support either reset method, but does not maintain state that
+needs the extra level of reset.
+@item
+On some platforms, this function does not set the stream error
+indicator on attempts to write to a read-only stream:
+glibc 2.13, Cygwin 1.7.9.