2 @subsection @code{advance}
7 Portability problems fixed by Gnulib:
11 Portability problems not fixed by Gnulib:
14 This function is missing on all non-glibc platforms:
15 Mac OS X 10.13, FreeBSD 6.0, NetBSD 9.0, OpenBSD 6.7, Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.