The HAVE_UNISTD_H change only shows up in configure because it's a fix
for shell code generated by an old autoconf release.

Submitted upstream:

  <https://lists.nongnu.org/archive/html/lynx-dev/2022-12/msg00000.html>

diff --git a/aclocal.m4 b/aclocal.m4
index 70cde243d2129cc0..bf2cbff661de2fe1 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -6435,6 +6435,7 @@ AC_CACHE_CHECK(if we can include termio.h with curses,cf_cv_termio_and_curses,[
     CPPFLAGS="$CPPFLAGS -DHAVE_CONFIG_H -I. -I${srcdir:-.} -I${srcdir:-.}/src -I${srcdir:-.}/WWW/Library/Implementation"
     touch lynx_cfg.h
     AC_TRY_COMPILE([
+#include <stdio.h>
 #include <$1>
 #include <termio.h>],
     [putchar(0x0a)],
@@ -6455,6 +6456,7 @@ AC_DEFUN([CF_TERMIO_AND_TERMIOS],
 AC_MSG_CHECKING([termio.h and termios.h])
 AC_CACHE_VAL(cf_cv_termio_and_termios,[
     AC_TRY_COMPILE([
+#include <stdio.h>
 #if HAVE_TERMIO_H
 #include <termio.h>
 #endif
diff --git a/configure b/configure
index 97f6d1d5646d05c5..6db52b514b3b9a3c 100755
--- a/configure
+++ b/configure
@@ -31122,6 +31122,7 @@ else
 #line 31122 "configure"
 #include "confdefs.h"
 
+#include <stdio.h>
 #if HAVE_TERMIO_H
 #include <termio.h>
 #endif
@@ -31629,6 +31630,9 @@ else
 #line 31629 "configure"
 #include "confdefs.h"
 /* Thanks to Mike Rendell for this test.  */
+#if HAVE_UNISTD_H
+# include <unistd.h>
+#endif
 #include <sys/types.h>
 #define NGID 256
 #undef MAX
@@ -47492,6 +47496,7 @@ else
 #line 47492 "configure"
 #include "confdefs.h"
 
+#include <stdio.h>
 #include <LYCurses.h>
 #include <termio.h>
 int