From 437e951db62848dcd75bfbc60542e243d45a5aa7 Mon Sep 17 00:00:00 2001
From: Ernie Pasveer <epasveer@att.net>
Date: Thu, 7 Sep 2023 17:57:30 -0500
Subject: [PATCH] Update mpi test program.

---
 tests/hellompi/Makefile                     |  7 ++++---
 tests/hellompi/{hellompi.c => hellompi.cpp} | 12 ++++++++++--
 2 files changed, 14 insertions(+), 5 deletions(-)
 rename tests/hellompi/{hellompi.c => hellompi.cpp} (63%)

diff --git a/tests/hellompi/Makefile b/tests/hellompi/Makefile
index f0faa27..0fbbc00 100644
--- a/tests/hellompi/Makefile
+++ b/tests/hellompi/Makefile
@@ -1,10 +1,11 @@
 EXECS=hellompi
-MPICC=/usr/lib64/mpi/gcc/openmpi4/bin/mpicc
+#MPICC=/usr/lib64/mpi/gcc/openmpi4/bin/mpicc
+MPI=/usr/lib64/mpi/gcc/mpich
 
 all: ${EXECS}
 
-hellompi: hellompi.c
-	${MPICC} -g -o hellompi hellompi.c
+hellompi: hellompi.cpp
+	g++ -g -I${MPI}/include -L${MPI}/lib64 -lmpi -o hellompi hellompi.cpp
 
 clean:
 	rm ${EXECS}
diff --git a/tests/hellompi/hellompi.c b/tests/hellompi/hellompi.cpp
similarity index 63%
rename from tests/hellompi/hellompi.c
rename to tests/hellompi/hellompi.cpp
index a6e4d66..75d7ed6 100644
--- a/tests/hellompi/hellompi.c
+++ b/tests/hellompi/hellompi.cpp
@@ -1,5 +1,7 @@
 #include <mpi.h>
-#include <stdio.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <iostream>
 
 int main(int argc, char** argv) {
 
@@ -20,7 +22,13 @@ int main(int argc, char** argv) {
     MPI_Get_processor_name(processor_name, &name_len);
 
     // Print off a hello world message
-    printf("Hello world from processor %s, rank %d out of %d processors\n", processor_name, world_rank, world_size);
+    std::cout << "Hello world from processor " << processor_name << " rank " << world_rank << " size " << world_size << std::endl;
+
+    std::cout << "Waiting for debugger to be attached, PID: " << getpid() << std::endl;
+
+    bool attached = false;
+
+    while (!attached) sleep(1);
 
     // Finalize the MPI environment.
     MPI_Finalize();