getdtablesize, dup2, fcntl: port to Android Problem reported by Kevin Cernekee in: http://lists.gnu.org/archive/html/bug-gnulib/2015-02/msg00092.html * doc/glibc-functions/getdtablesize.texi (getdtablesize): Mention that getdtablesize doesn't work on Android. * lib/getdtablesize.c: Use getrlimit substitute only if getdtablesize is declared. This should suffice for Cygwin while not breaking Android. * m4/dup2.m4 (gl_FUNC_DUP2): * m4/fcntl.m4 (gl_FUNC_FCNTL): Prefer sysconf (_SC_OPEN_MAX) to getdtablesize, as the former is standardized but the latter is not, and sysconf works on Android. * m4/getdtablesize.m4 (gl_FUNC_GETDTABLESIZE): Also check that getdtablesize is declared. This removes the need for a special case for Android.