--- a/ChangeLog	Mon Oct 01 14:57:45 2018 -0600
+++ b/ChangeLog	Tue Oct 02 01:17:34 2018 +0200
@@ -1,3 +1,9 @@
+2018-10-01  Bruno Haible  <bruno@clisp.org>
+
+	mkostemp, mkostemps: Update documentation.
+	* doc/glibc-functions/mkostemp.texi: Mention the Mac OS X issue.
+	* doc/glibc-functions/mkostemps.texi: Likewise.
+
 2018-10-01  Tom Tromey  <tom@tromey.com>
 
 	mkostemp, mkostemps: Fix compilation error in C++ mode on Mac OS X.

--- a/doc/glibc-functions/mkostemp.texi	Mon Oct 01 14:57:45 2018 -0600
+++ b/doc/glibc-functions/mkostemp.texi	Tue Oct 02 01:17:34 2018 +0200
@@ -10,6 +10,10 @@
 This function is missing on many non-glibc platforms:
 Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, OSF/1 5.1, Solaris 11.3, Cygwin 1.7.5, mingw, MSVC 14, Interix 3.5, BeOS, Android 5.1.
 @item
+This function is declared in @code{<unistd.h>} instead of @code{<stdlib.h>}
+on some platforms:
+Mac OS X 10.13.
+@item
 On platforms where @code{off_t} is a 32-bit type, @code{mkostemp} may not work
 correctly to create files larger than 2 GB.  (Cf. @code{AC_SYS_LARGEFILE}.)
 @end itemize

--- a/doc/glibc-functions/mkostemps.texi	Mon Oct 01 14:57:45 2018 -0600
+++ b/doc/glibc-functions/mkostemps.texi	Tue Oct 02 01:17:34 2018 +0200
@@ -10,6 +10,10 @@
 This function is missing on many non-glibc platforms:
 glibc 2.10, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, IRIX 6.5, OSF/1 5.1, Solaris 11.3, Cygwin 1.7.5, mingw, MSVC 14, Interix 3.5, BeOS, Android 5.1.
 @item
+This function is declared in @code{<unistd.h>} instead of @code{<stdlib.h>}
+on some platforms:
+Mac OS X 10.13.
+@item
 On platforms where @code{off_t} is a 32-bit type, @code{mkostemps} may not work
 correctly to create files larger than 2 GB.  (Cf. @code{AC_SYS_LARGEFILE}.)
 @end itemize