diff --git a/programs/dxdiag/main.c b/programs/dxdiag/main.c
index d24945c..5edfc6e 100644
--- a/programs/dxdiag/main.c
+++ b/programs/dxdiag/main.c
@@ -20,8 +20,77 @@
 
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
+#include "wine/debug.h"
 
-int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR cmdline, int cmdshow)
+WINE_DEFAULT_DEBUG_CHANNEL(dxdiag);
+
+/*
+    Process options [/WHQL:ON|OFF][/X outfile][/T outfile]
+    Returns TRUE if options were present, FALSE otherwise
+    FIXME: Native behavior seems to be:
+    Only one of /X and /T is allowed, /WHQL must come before /X and /T,
+    quotes are optional around the filename, even if it contains spaces.
+*/
+
+static BOOL ProcessCommandLine(LPWSTR cmdline)
+{
+    const WCHAR *s = cmdline;
+    WCHAR outfile[MAX_PATH+1];
+    int opt_t = FALSE;
+    int opt_x = FALSE;
+    int opt_help = FALSE;
+    int opt_given = FALSE;
+    int want_arg = FALSE;
+
+    outfile[0] = 0;
+    while (*s) {
+        /* Skip whitespace before arg */
+        while (*s == ' ')
+            s++;
+        /* Check for option */
+        if (*s != '-' && *s != '/')
+            return FALSE;
+        s++;
+        switch (*s++) {
+        case 'T':
+        case 't': opt_t = TRUE; want_arg = TRUE; opt_given = TRUE; break;
+        case 'X':
+        case 'x': opt_x = TRUE; want_arg = TRUE; opt_given = TRUE; break;
+        case 'W':
+        case 'w':
+            opt_given = TRUE;
+            while (isalpha(*s) || *s == ':') 
+                s++; 
+            break;
+        default: opt_help = TRUE; opt_given = TRUE; break;
+        }
+        /* Skip any spaces before next option or filename */
+        while (*s == ' ')
+            s++;
+        if (want_arg) {
+            int i;
+            if (*s == '"')
+                s++;
+            for (i=0; i < MAX_PATH && *s && *s != '"'; i++, s++)
+                outfile[i] = *s;
+            outfile[i] = 0;
+            break;
+        }
+    }
+    if (opt_help)
+        WINE_FIXME("help unimplemented\n");
+    if (opt_t)
+        WINE_FIXME("/t unimplemented\n");
+    if (opt_x)
+        WINE_FIXME("/x unimplemented\n");
+    return opt_given;
+}
+
+int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR lpcmdline, int cmdshow)
 {
+    WCHAR *cmdline = GetCommandLineW();
+    if (ProcessCommandLine(cmdline))
+        return 0;
+
     return 0;
 }