From 3acb81ca23207634aef1a7924a64a1cfa672a7a7 Mon Sep 17 00:00:00 2001
From: Carl Pearson <cwpears@sandia.gov>
Date: Fri, 30 Apr 2021 14:54:39 -0600
Subject: [PATCH] update README

---
 README.md | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/README.md b/README.md
index e05ca7e..2865d24 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,25 @@
 # mpi_test
+
+Various standalone MPI binaries
+* all pass `argc`/`argv` to `MPI_Init`
+
+Adjust `Makefile` to match your environment, if needed
+* uses `mpicxx` and a few simple flags by default
+
+## Build
+```
+make
+```
+
+## Run all tests
+
+Adjust `run-all.sh` to match your environment, if needed
+```
+./run-all.sh
+```
+
+If any tests fail, you can run them individually.
+
+## Run individual tests
+
+Execute any binary you want using `mpirun`, or whatever is appropriate for your platform.
\ No newline at end of file