Include unistd.h, if it exists.

diff --git a/src/xfns.c b/src/xfns.c
index bd7894774b778b52caadc236d79c863b190cafe5..836e2d4c82704dcb2be08d232c9115cf92502ee6 100644 (file)
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -24,6 +24,10 @@ Boston, MA 02111-1307, USA.  */
 #include <stdio.h>
 #include <math.h>
 
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
 /* This makes the fields of a Display accessible, in Xlib header files.  */
 
 #define XLIB_ILLEGAL_ACCESS