-#endif /* __svr4__ */
-
-#ifdef linux
-/*
- * Linux has SA_RESTART, but no SA_INTERRUPT. Note that the documentation
- * seems to be wrong on several counts. First, SA_ONESHOT is not the default,
- * and second, SA_RESTART does what you'd expect (the same as svr4) and has
- * nothing to do with SA_ONESHOT.
- */
-#ifndef SA_INTERRUPT
-#define SA_INTERRUPT 0
-#endif /* SA_INTERRUPT */
-#endif /* linux */
-
-#ifdef ultrix
-#include <sys/types.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-
-/*
- * Here's the really confusing one... Under Ultrix, sigaction() works just
- * like sigvec(), except that SV_INTERRUPT is always set. Hence, there is
- * no SA_INTERRUPT flag. Unfortunately, there's also no SA_RESTART, so
- * there's no way to suppress the interrupt. Sigh.
- */
-#ifndef SA_INTERRUPT
-#define SA_INTERRUPT 0
-#endif
-#ifndef SA_RESTART
-#define SA_RESTART 0