2 files changed, 21 insertions, 0 deletions
diff --git a/src/platform/posix/posix_thread.c b/src/platform/posix/posix_thread.c
index f016ca3f..df2ee9d2 100644
--- a/src/platform/posix/posix_thread.c
+++ b/src/platform/posix/posix_thread.c
@@ -336,4 +336,16 @@ nni_plat_fini(void)
 	pthread_mutex_unlock(&nni_plat_init_lock);
 }
 
+int
+nni_plat_ncpu(void)
+{
+	// POSIX specifies sysconf exists, but not the value
+	// _SC_NPROCESSORS_ONLN.  Nonetheless, everybody implements it.
+	// If you don't we'll assume you only have a single logical CPU.
+#ifdef _SC_NPROCESSORS_ONLN
+	return (sysconf(_SC_NPROCESSORS_ONLN));
+#else
+	return (1);
+#endif
+}
 #endif // NNG_PLATFORM_POSIX
diff --git a/src/platform/windows/win_thread.c b/src/platform/windows/win_thread.c
index 2e9d58d7..a3d932aa 100644
--- a/src/platform/windows/win_thread.c
+++ b/src/platform/windows/win_thread.c
@@ -148,6 +148,15 @@ nni_plat_thr_is_self(nni_plat_thr *thr)
 static LONG plat_inited = 0;
 
 int
+nni_plat_ncpu(void)
+{
+	SYSTEM_INFO info;
+
+	GetSystemInfo(&info);
+	return ((int) (info.dwNumberOfProcessors));
+}
+
+int
 nni_plat_init(int (*helper)(void))
 {
 	int            rv   = 0;