diff --git a/include/sys/sysinfo.h b/include/sys/sysinfo.h
index 489f56b..eb5b4c7 100644
--- a/include/sys/sysinfo.h
+++ b/include/sys/sysinfo.h
@@ -48,14 +48,16 @@ __BEGIN_DECLS
 /* Returns information on overall system statistics.  */
 extern int sysinfo (struct sysinfo *__info) __THROW;
 
-#if 0
+#ifdef __USE_GNU
 /* Return number of configured processors.  */
-extern int get_nprocs_conf (void) __THROW;
+/* extern int get_nprocs_conf (void) __THROW; */
+#define get_nprocs_conf() ((int)sysconf(_SC_NPROCESSORS_CONF))
 
 /* Return number of available processors.  */
-extern int get_nprocs (void) __THROW;
-
-
+/*extern int get_nprocs (void) __THROW; */
+#define get_nprocs() ((int)sysconf(_SC_NPROCESSORS_ONLN))
+#endif
+#if 0
 /* Return number of physical pages of memory in the system.  */
 extern long int get_phys_pages (void) __THROW;
 
