diff --git a/kernel.c b/kernel.c
index e7e70c7..a4ca0a3 100644
--- a/kernel.c
+++ b/kernel.c
@@ -212,7 +212,7 @@ void PrintFileList() {
         vga_text = nextLine(vga_text) + 3;
     }
 }
-extern void create_child(uint32_t esp, uint32_t eip);
+extern void create_child(uint32_t esp, uint32_t eip, uint32_t argc, ...);
 void FileSelect() {
     fileCount = 5;
     uint16_t *vga_text = (uint16_t *)0xb8000;
@@ -245,21 +245,23 @@ void FileSelect() {
                 if (fileHovered < 0) fileHovered = fileCount - 1;
                 break;
             case 0x14: // t
-                create_child(0x3C0000, (uintptr_t)RunTests);
+                create_child(0x380000, (uintptr_t)RunTests, 0);
                 SetCursorDisabled();
                 DrawScreen();
                 reload = 1;
                 break;
             case KEY_X:
                 File83ToPath((char*)entries[fileHovered].name, (char*)path);
-                HexViewTest(path, &vi);
+                //HexViewTest(path, &vi);
+                create_child(0x380000, (uintptr_t)HexViewTest, 2, path, &vi);
                 SetVideo25Lines();
                 SetCursorDisabled();
                 DrawScreen();
                 break;
             case KEY_V:
                 File83ToPath((char*)entries[fileHovered].name, (char*)path);
-                TextViewTest(path, &vi);
+                //TextViewTest(path, &vi);
+                create_child(0x380000, (uintptr_t)TextViewTest, 2, path, &vi);
                 SetVideo25Lines();
                 SetCursorDisabled();
                 DrawScreen();
@@ -321,10 +323,10 @@ void start() {
     vga_text += printStr("Press T for tests, or any key to continue... ", vga_text);
     uint8_t key = get_key();
     if (key == 't' || key == 'T')
-        RunTests(vga_text);
-    DrawScreen();
+        create_child(0x380000, (uintptr_t)RunTests, 0);
     SetVideo25Lines();
     SetCursorDisabled();
+    DrawScreen();
     FileSelect();
 }
 
diff --git a/task.nasm b/task.nasm
index 657df10..3e256da 100644
--- a/task.nasm
+++ b/task.nasm
@@ -7,16 +7,25 @@ ret
 global task_ptr
 task_ptr: equ (0x310000-4)
 
-
-; extern void create_child(uint32_t esp, uint32_t eip);
+; TODO Is varargs too compiler dependent?
+; extern void create_child(uint32_t esp, uint32_t eip, uint32_t argc, ...);
 global create_child
 create_child:
+xchg bx,bx
 mov eax, [esp] ; return address
 lea ecx, [esp+4] ; return stack, minus address
 call save_current_task
-xchg bx,bx
 mov eax, [esp+8] ; new eip
+mov ecx, [esp+12] ; argc
+mov esi, esp ; old esp
 mov esp, [esp+4] ; new esp
+lea esi, [esi+16] ; args
+mov edx, ecx
+neg edx
+lea esp, [esp+edx*4] ; adjust for args
+mov edi, esp
+; copy varargs to new stack
+rep movsd
 push return_prev_task ; if child returns, return to prev task
 push eax
 ret