--- configure.in.~1~	Tue Aug  3 13:36:22 1999
+++ configure.in	Thu Nov 18 06:45:50 1999
@@ -69,6 +69,7 @@
 dnl ##### Checks for header files.
 AC_PATH_XTRA
 AC_HEADER_DIRENT
+AC_CHECK_HEADERS(unistd.h)
 
 dnl ##### Look for header that defines fd_set.
 AC_MSG_CHECKING([fd_set and sys/select.h or sys/bsdtypes.h])
@@ -147,6 +148,9 @@
 xpdf_cv_func_select_arg,
 [AC_TRY_COMPILE([#include <sys/types.h>
 #include <sys/time.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
 #ifdef HAVE_SYS_SELECT_H
 #include <sys/select.h>
 #endif],
