+2012-09-13 Paolo Bonzini <bonzini@gnu.org>
+
+ poll/select: document portability problems not fixed by Gnulib.
+ * doc/posix-functions/poll.texi: poll does not work well on
+ pipes under Windows. It has the same limitations as select on
+ BeOS.
+ * doc/posix-functions/select.texi: select does not work well
+ on pipes under Windows.
+
2012-09-10 Paul Eggert <eggert@cs.ucla.edu>
fcntl-h: check for AIX 7.1 bug with O_NOFOLLOW and O_CREAT
Portability problems not fixed by Gnulib:
@itemize
+@item
+Under BeOS, Gnulib's @code{poll} replacement can only be called on descriptors
+created by the @code{socket} function, not on regular file descriptors.
+
+@item
+Under Windows, when passing a pipe, Gnulib's @code{poll} replacement might
+return 0 even before the timeout has passed. Programs using it with pipes can
+thus busy wait.
@end itemize
On BeOS, @code{select} can only be called on descriptors created by the
@code{socket} function, not on regular file descriptors.
@item
+Under Windows, when passing a pipe, Gnulib's @code{select} replacement might
+return 0 even before the timeout has passed. Programs using it with pipes can
+thus busy wait.
+@item
On Solaris 2.6 and older, @code{select} applied to a file descriptor opened
for reading and associated with @code{/dev/null} hangs, waiting for input,
when instead it should return immediately.