added commandline args incl. script dir selection; handle ctrl+c

pier.py

 #!/usr/bin/env python3
 
+DIR  = "."
+HOST = "localhost"
+PORT = 9090
+
+
+import argparse
+
+parser = argparse.ArgumentParser(
+    description="pier - Python Interpreter Executing Remotely",
+    formatter_class=argparse.ArgumentDefaultsHelpFormatter
+)
+
+parser.add_argument("-d", "--dir",  default=DIR,  help="directory containing python scripts")
+parser.add_argument("-H", "--host", default=HOST, help="host name")
+parser.add_argument("-P", "--port", default=PORT, help="port number", type=int)
+
+clargs = parser.parse_args()
+
+
 from contextlib import redirect_stdout, redirect_stderr
 from functools import lru_cache
 from glob import glob
 from io import StringIO
 
+import os
 import http.server
 import socketserver
 
 
-HOST = "localhost"
-PORT = 9090
-
-
 class ScriptServer(http.server.SimpleHTTPRequestHandler):
 
     def do_GET(self):
@@ -71,10 +87,23 @@ def encode_html(*msg):
 
 
 if __name__ == "__main__":
+    try:
+        os.chdir(clargs.dir)
+    except Exception as e:
+        tn = type(e).__name__
+        msg = f"{tn}: {e}"
+        raise SystemExit(msg)
+
+    host = clargs.host
+    port = clargs.port
+
     socketserver.TCPServer.allow_reuse_address = True
-    with socketserver.ThreadingTCPServer((HOST, PORT), ScriptServer) as httpd:
-        print(f"serving at {HOST}:{PORT}")
-        httpd.serve_forever()
+    with socketserver.ThreadingTCPServer((host, port), ScriptServer) as httpd:
+        print(f"serving at {host}:{port}")
+        try:
+            httpd.serve_forever()
+        except KeyboardInterrupt:
+            print()