diff -r 868db5c1f2d7 -r e29384105b8d setup/setup.c
--- a/setup/setup.c	Thu Aug 13 19:01:16 2009 +0100
+++ b/setup/setup.c	Fri Mar 23 20:29:50 2012 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009  J. Ali Harlow <ali@juiblex.co.uk>
+ * Copyright (C) 2009, 2011  J. Ali Harlow <ali@juiblex.co.uk>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -75,21 +75,10 @@
     free(vector);
 }
 
-static void *alloc_lua(void *user_data,void *ptr,size_t osize,size_t nsize)
-{
-    if (!nsize)
-    {
-	free(ptr);
-	return NULL;
-    }
-    else
-	return realloc(ptr,nsize);
-}
-
 void setup(const char *argv0)
 {
     char *path,*s,*prefix;
-    int changed;
+    int ch,changed;
     struct comps *comps;
     struct comps_group *group;
     struct comps_requirement *pkg;
@@ -104,6 +93,18 @@
     }
     free(s);
     prefix=plover_default_prefix_for_vendor(comps->vendor);
+    if (!plover_installed_files_match_prefix(prefix))
+    {
+	printf("The existing installation is not under %s\n"
+	  "In order to continue, all the existing packages must be removed.\n"
+	  "Do you want to remove all existing packages? ",prefix);
+	ch=getchar();
+	if (ch!='y' && ch!='Y' && ch!=EOF && ch!='\n')
+	    exit(1);
+	while(ch!='\n' && ch!=EOF)
+	    ch=getchar();
+	plover_remove(NULL);
+    }
     group=plover_comps_lookup_group(comps,"base");
     if (!group)
     {
@@ -148,4 +149,5 @@
 	plover_remove(NULL);
     else
 	setup(argv[0]);
+    exit(0);
 }