=== modified file 'ppio.nim'
--- ppio.nim	2019-04-01 12:45:58 +0000
+++ ppio.nim	2019-04-01 12:39:56 +0000
@@ -10,13 +10,13 @@
   write(stdout, "writeVersion()\n")
   quit(0)
 
-# proc posixPrintArgs(): void =
-#   var argc = paramCount()
-#   for n in countup(1, argc):
-#     echo "  [" & paramStr(n) & "]"
-#   echo "---"
-#   for s in commandLineParams():
-#     echo "  [" & s & "]"
+proc posixPrintArgs(): void =
+  var argc = paramCount()
+  for n in countup(1, argc):
+    echo "  [" & paramStr(n) & "]"
+  echo "---"
+  for s in commandLineParams():
+    echo "  [" & s & "]"
 
 type
   Args = tuple[
@@ -66,10 +66,28 @@
     inc(n)
   return args
 
-proc main(): void =
+proc main(cmdline = ""): void =
+  var filename = ""
+  var p = initOptParser(cmdline)
+  write(stdout, "cmdline: " & repr(p.cmd) & "\n")
+  for a in os.parseCmdLine(p.cmd):
+    echo "  «" & a & "»"
   var args = posixParseArgs()
-  write(stderr, "args: " & repr(args) & "\n")
-  if len(args.exe) == 0:
+  write(stdout, "args: " & repr(args) & "\n")
+  for kind, key, val in p.getopt():
+    case kind
+    of cmdArgument:
+      write(stdout, "cmdArgument: " & repr(key) & "\n")
+      filename = key
+    of cmdLongOption, cmdShortOption:
+      write(stdout, "option: " & repr(key) & "\n")
+      case key
+      of "": break
+      of "help", "h": writeHelp(0)
+      of "version", "v": writeVersion()
+    of cmdEnd: assert(false) # cannot happen
+  if filename == "":
+    # no filename has been given, so we show the help:
     echo "No arguments"
     writeHelp(1)