doc: Mention reason for replacement on glibc/Linux systems. * doc/posix-functions/dprintf.texi: Mention the problem with special 'long double' values. * doc/posix-functions/fprintf.texi: Likewise. * doc/posix-functions/printf.texi: Likewise. * doc/posix-functions/snprintf.texi: Likewise. * doc/posix-functions/sprintf.texi: Likewise. * doc/posix-functions/vdprintf.texi: Likewise. * doc/posix-functions/vfprintf.texi: Likewise. * doc/posix-functions/vprintf.texi: Likewise. * doc/posix-functions/vsnprintf.texi: Likewise. * doc/posix-functions/vsprintf.texi: Likewise. * doc/posix-functions/fcntl.texi: Add glibc/Linux to the list of platforms with F_DUPFD_CLOEXEC problems. * doc/posix-functions/glob.texi: Mention which platforms are affected by the problem with symbolic links. * doc/posix-functions/linkat.texi: Mention the problem with AT_SYMLINK_FOLLOW on Linux.

@node posix_openpt
@section @code{posix_openpt}
@findex posix_openpt

POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/posix_openpt.html}

Gnulib module: posix_openpt

Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
MacOS X 10.3, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.23, IRIX 6.5, OSF/1 5.1,
Solaris 9, Cygwin 1.5.x, mingw, MSVC 9, Interix 3.5, BeOS.
However, the replacement may fail with @code{ENOSYS} or @code{ENOENT} on
some platforms.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@end itemize

Note that when using this function to open the master side of a
pseudo-terminal, you still need platform dependent code to open the
corresponding slave side.  The Gnulib module @code{openpty} provides
an easy-to-use API that does both at once.