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 link
@section @code{link}
@findex link

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

Gnulib module: link

Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
mingw, MSVC 9.
@item
This function fails to reject trailing slashes on non-directories on
some platforms:
FreeBSD 7.2, Solaris 11 2011-11, Cygwin 1.5.x.
@item
When the second argument is a dangling symlink, some platforms follow
that link and create the destination rather than failing:
IRIX 6.5.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
When the first argument is a symlink, some platforms create a
hard-link to what the symlink referenced, rather than to the symlink
itself.  Use @samp{linkat} to force a particular behavior.
@end itemize