From: Ian Jackson <ian@davenant.relativity.greenend.org.uk>
Date: Sat, 27 Sep 2008 15:02:47 +0000 (+0100)
Subject: add nprocessors utility
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=moebius2.git;a=commitdiff_plain;h=b70945de51cdfbec31a3cce4382c7f41cdb4895c

add nprocessors utility
---

diff --git a/Makefile b/Makefile
index b41c543..d3ddd4f 100644
--- a/Makefile
+++ b/Makefile
@@ -31,6 +31,9 @@ minimise:	energy.o graph.o common.o mgraph.o minimise.o half.o
 primer:		primer.o common.o
 		$(CC) $(CFLAGS) -o $@ $^ $(LIBGSL)
 
+nprocessors:	nprocessors.o common.o
+		$(CC) $(CFLAGS) -o $@ $^ $(LIBGSL)
+
 prime.data:	primer
 		./$^ $o
 
diff --git a/nprocessors.c b/nprocessors.c
new file mode 100644
index 0000000..b15bf8e
--- /dev/null
+++ b/nprocessors.c
@@ -0,0 +1,16 @@
+/*
+ * prints number of processors
+ */
+
+#include <unistd.h>
+
+#include "common.h"
+
+int main(int argc, char **argv) {
+  if (argc!=1) fail("usage: nprocessors\n");
+  long sc= sysconf(_SC_NPROCESSORS_ONLN);
+  if (sc==-1) diee("nprocessors: sysconf failed");
+  printf("%ld\n",sc);
+  flushoutput();
+  return 0;
+}