+#if USE_PTHREADS_EINTR
+# if USE_WEAK_SYMBOLS
+#include <pthread.h>
+weak_symbol(pthread_sigmask);
+weak_symbol(pthread_kill);
+weak_symbol(pthread_self);
+weak_symbol(pthread_equal);
+extern NCURSES_EXPORT(int) _nc_sigprocmask(int, const sigset_t *, sigset_t *);
+# undef sigprocmask
+# define sigprocmask _nc_sigprocmask
+# endif
+#endif /* USE_PTHREADS_EINTR */
+