1 files changed, 16 insertions, 0 deletions

diff --git a/shells/sub_bash.nix b/shells/sub_bash.nix
new file mode 100644
index 0000000..656b385
--- /dev/null
+++ b/shells/sub_bash.nix
@@ -0,0 +1,16 @@
+# run with
+# nix-shell shell.nix --run 'touch in ; tail -f in | bash & echo $! > pid'
+# and then send commands with
+# echo 'compute_me "1 + 3"' >> in
+{ pkgs ? import <nixpkgs> {} }:
+pkgs.mkShell {
+  buildInputs = [ pkgs.bc ];
+  shellHook = ''
+    compute_me() {
+      echo "$1" | bc;
+    }
+    export -f compute_me
+
+    echo "I’m ready"
+    '';
+}