Iczelion's Tutorial 12: Memory Management and File I/O

in this tutorial it says :

Quote:

1. Allocate a block of memory by calling GlobalAlloc. This function returns a handle to the requested memory block.
2. "Lock" the memory block by calling GlobalLock. This function accepts a handle to the memory block and returns a pointer to the memory block.
3. You can use the pointer to read or write memory.
4. "Unlock" the memory block by calling GlobalUnlock . This function invalidates the pointer to the memory block.
5. Free the memory block by calling GlobalFree. This function accepts the handle to the memory block.

The above method can be further simplified by using a flag in GlobalAlloc call, GMEM_FIXED. If you use this flag, the return value from Global/LocalAlloc will be the pointer to the allocated memory block, not the memory block handle. You don't have to call Global/LocalLock and you can pass the pointer to Global/LocalFree without calling Global/LocalUnlock first.

so I changed the code to this:

Code:

                invoke  GlobalAlloc,GMEM_MOVEABLE + GMEM_ZEROINIT + GMEM_FIXED,MEM_SIZE
;                mov     [hMem],eax
;                invoke  GlobalLock,eax
                mov     [pMem],eax
                invoke  ReadFile,[hFile],[pMem],MEM_SIZE-1,szReadWrite,NULL
                invoke  SendMessage,[hEdit],WM_SETTEXT,NULL,[pMem]
                invoke  CloseHandle,[hFile]
;                invoke  GlobalUnlock,[pMem]
                invoke  GlobalFree,[hMem]

but with this code when I open a file it puts out only 3 strange symbols. What am I doing whrong ?
Also when I looked up GlobalAlloc on MSDN and it says : "Note The global functions are slower than other memory management functions and do not provide as many features. Therefore, new applications should use the heap functions." so should I use them, or something else ?