+AC_SUBST(SP_PKGLIBS)
+
+# Checks for header files.
+# These are already checked: inttypes.h dlfcn.h memory.h stdint.h stdlib.h
+# string.h strings.h sys/types.h sys/stat.h unistd.h
+AC_CHECK_HEADERS([errno.h fcntl.h stddef.h sys/ioctl.h termios.h])
+