From 329c9f6217af87786d253a12e0f33f3470e8b404 Mon Sep 17 00:00:00 2001
From: David Kaufmann <astra@ionic.at>
Date: Thu, 26 Jan 2012 22:45:39 +0100
Subject: [PATCH] add mpi

---
 openmp/scan/Makefile | 20 ++++++++++++++++++++
 openmp/scan/scan.c   | 37 +++++++++++++++++++++++++++++++++++++
 openmp/scan/scan.h   |  3 +++
 3 files changed, 60 insertions(+)
 create mode 100644 openmp/scan/Makefile
 create mode 100644 openmp/scan/scan.c
 create mode 100644 openmp/scan/scan.h

diff --git a/openmp/scan/Makefile b/openmp/scan/Makefile
new file mode 100644
index 0000000..8b34472
--- /dev/null
+++ b/openmp/scan/Makefile
@@ -0,0 +1,20 @@
+# GCC Makefile
+
+CC      = mpicc
+CFLAGS  = -pedantic -Wall -ggdb -fopenmp --std=c99 -O3 ${MYFLAGS}
+LDFLAGS = -fopenmp
+
+all: build/scan
+
+build/scan: build/scan.o
+	$(CC) -o $@ $? $(LDFLAGS)
+
+build/%.o: %.c mkdir
+	$(CC) $(CFLAGS) -c $< -o $@
+
+mkdir:
+	mkdir -p build
+
+.PHONY: clean
+clean:
+	rm -rf build
diff --git a/openmp/scan/scan.c b/openmp/scan/scan.c
new file mode 100644
index 0000000..ec1029e
--- /dev/null
+++ b/openmp/scan/scan.c
@@ -0,0 +1,37 @@
+/*
+ * Inclusive scan
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "scan.h"
+#include <mpi.h>
+
+#define KEY 1234 // tag for control messages
+
+int main(int argc, char *argv[])
+{
+  int rank, size;
+  int prev;
+  char name[MPI_MAX_PROCESSOR_NAME];
+  int nlen;
+
+  MPI_Init(&argc,&argv);
+
+  // get rank and size from communicator
+  MPI_Comm_size(MPI_COMM_WORLD,&size);
+  MPI_Comm_rank(MPI_COMM_WORLD,&rank);
+
+  MPI_Get_processor_name(name,&nlen);
+
+  if (rank==0) {
+    printf("Rank %d initializing, total %d\n",rank,size);
+  } else {
+    MPI_Recv(&prev,1,MPI_INT,rank-1,HELLO,MPI_COMM_WORLD,MPI_STATUS_IGNORE);
+    printf("Rank %d on %s received from %d, passing on\n",rank,name,prev);
+  }
+  if (rank+1<size) MPI_Send(&rank,1,MPI_INT,rank+1,HELLO,MPI_COMM_WORLD);
+      
+  MPI_Finalize();
+  return 0;
+}
diff --git a/openmp/scan/scan.h b/openmp/scan/scan.h
new file mode 100644
index 0000000..0a496a3
--- /dev/null
+++ b/openmp/scan/scan.h
@@ -0,0 +1,3 @@
+/*
+ * Inclusive scan - header
+ */
-- 
2.43.0