doc: Document <link.h>

[Bruno Haible]

The Gnulib documentation has a section regarding the function
'dl_iterate_phdr', but not regarding the header file which declares
this function. This makes no sense.


2020-11-22  Bruno Haible  <bruno@clisp.org>

        doc: Document <link.h>.
        * doc/glibc-headers/link.texi: New file.
        * doc/gnulib.texi: Include it.

diff --git a/doc/glibc-headers/link.texi b/doc/glibc-headers/link.texi
new file mode 100644
index 0000000..08ca56f
--- /dev/null
+++ b/doc/glibc-headers/link.texi
@@ -0,0 +1,20 @@
+@node link.h
+@section @file{link.h}
+
+Defines the type @code{struct dl_phdr_info}, and declares the function
+@code{dl_iterate_phdr}.
+
+Documentation: ---
+
+Gnulib module: ---
+
+Portability problems fixed by Gnulib:
+@itemize
+@end itemize
+
+Portability problems not fixed by Gnulib:
+@itemize
+@item
+This header file is missing on some platforms:
+Mac OS X 10.13, AIX 7.1, HP-UX 11.31, IRIX 6.5, Cygwin 2.9.0, mingw, MSVC 14.
+@end itemize
diff --git a/doc/gnulib.texi b/doc/gnulib.texi
index c4bf8b1..0620118 100644
--- a/doc/gnulib.texi
+++ b/doc/gnulib.texi
@@ -3673,6 +3673,7 @@ not worked around by Gnulib.
 * ieee754.h::
 * ifaddrs.h::
 * libintl.h::
+* link.h::
 * mcheck.h::
 * mntent.h::
 * obstack.h::
@@ -3708,6 +3709,7 @@ not worked around by Gnulib.
 @include glibc-headers/ieee754.texi
 @include glibc-headers/ifaddrs.texi
 @include glibc-headers/libintl.texi
+@include glibc-headers/link.texi
 @include glibc-headers/mcheck.texi
 @include glibc-headers/mntent.texi
 @include glibc-headers/obstack.texi