the last parameter of XChangeProperty is the number of elements.. and when the element format is 32.. the element is "long" so we have 5 long elements here.

Yes this seems confusing as on mac+linux Long is either 32 or 64bits depending on the architecture, but this is how the X11 protocol is defined. Thus 5 is the correct value for the nelts here.  Not 5 or 10 depending on the architecture.

More info on the confusion https://bugs.freedesktop.org/show_bug.cgi?id=16802

visualtest/unittest/testquit.actions

@@ -0,0 +1 @@
+00:00:05 QUIT

visualtest/unittest/testquit.c

@@ -0,0 +1,101 @@
+/*
+  Copyright (C) 2013 Apoorv Upreti <apoorvupreti@gmail.com>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely.
+*/
+/* Quits, hangs or crashes based on the command line options passed. */
+
+#include <SDL.h>
+#include <SDL_test.h>
+
+static SDLTest_CommonState *state;
+static int exit_code;
+static SDL_bool hang;
+static SDL_bool crash;
+
+int
+main(int argc, char** argv)
+{
+    int i, done;
+    SDL_Event event;
+
+    state = SDLTest_CommonCreateState(argv, SDL_INIT_VIDEO);
+    if(!state)
+        return 1;
+
+    state->window_flags |= SDL_WINDOW_RESIZABLE;
+    
+    exit_code = 0;
+    hang = SDL_FALSE;
+    crash = SDL_FALSE;
+
+    for(i = 1; i < argc; )
+    {
+        int consumed;
+        consumed = SDLTest_CommonArg(state, i);
+        if(consumed == 0)
+        {
+            consumed = -1;
+            if(SDL_strcasecmp(argv[i], "--exit-code") == 0)
+            {
+                if(argv[i + 1])
+                {
+                    exit_code = SDL_atoi(argv[i + 1]);
+                    consumed = 2;
+                }
+            }
+            else if(SDL_strcasecmp(argv[i], "--hang") == 0)
+            {
+                hang = SDL_TRUE;
+                consumed = 1;
+            }
+            else if(SDL_strcasecmp(argv[i], "--crash") == 0)
+            {
+                crash = SDL_TRUE;
+                consumed = 1;
+            }
+        }
+
+        if(consumed < 0)
+        {
+            SDLTest_Log("Usage: %s %s [--exit-code N] [--crash] [--hang]", argv[0], SDLTest_CommonUsage(state));
+            SDLTest_CommonQuit(state);
+            return 1;
+        }
+        i += consumed;
+    }
+
+    if(!SDLTest_CommonInit(state))
+    {
+        SDLTest_CommonQuit(state);
+        return 1;
+    }
+
+    /* infinite loop to hang the process */
+    while(hang)
+        SDL_Delay(10);
+
+    /* dereference NULL pointer to crash process */
+    if(crash)
+    {
+        int* p = NULL;
+        *p = 5;
+    }
+
+    /* event loop */
+    done = 0;
+    while(!done)
+    {
+        while(SDL_PollEvent(&event))
+            SDLTest_CommonEvent(state, &event, &done);
+        SDL_Delay(10);
+    }
+
+    return exit_code;
+}

visualtest/unittest/testquit.config

@@ -0,0 +1,5 @@
+sutconfig=testquit.parameters
+action-config=testquit.actions
+variator=exhaustive
+sutapp=testquit
+timeout=00:00:10

visualtest/unittest/testquit.parameters

@@ -0,0 +1,3 @@
+--exit-code, integer, [-1 1], false, [] # The exit code returned by the executable
+--crash, boolean, [], false, [] # Crashes the SUT executable
+--hang, boolean, [], false, [] # Runs the SUT in the infinite loop and ignores all events