+// many versions of Unices have this function, but it is not defined in system
+// headers - please add your system here if it is the case for your OS.
+// SunOS < 5.6 (i.e. Solaris < 2.6) and DG-UX are like this.
+#if (defined(__SUN__) && !defined(__SunOs_5_6) && \
+ !defined(__SunOs_5_7) && !defined(__SUNPRO_CC)) || \
+ defined(__osf__)
+ extern "C"
+ {
+ void usleep(unsigned long usec);
+ };
+#endif // Unices without usleep()
+