HANDLE GlobalAlloc(wFlags,dwBytes)
This function allocates the number of bytes of memory specified by the dwBytes parameter from the global heap. The memory can be fixed or moveable, depending on the memory type specified by the wFlags parameter.
| Parameter | Type/Description |
| wFlags | WORD Specifies one or more flags that tell the GlobalAlloc function how to allocate the memory. It can be one or more of the following values: | ||
| Value | Meaning | ||
| GMEM_DDESHARE | Allocates sharable memory. This is used for dynamic data exchange (DDE) only. Note, however, that Windows automatically discards memory allocated with this attribute when the application that allocated the memory terminates. | ||
| GMEM_DISCARDABLE | Allocates discardable memory. Can only be used with GMEM_MOVEABLE. | ||
| GMEM_FIXED | Allocates fixed memory. | ||
| GMEM_MOVEABLE | Allocates moveable memory. Cannot be used with GMEM_FIXED. | ||
| GMEM_NOCOMPACT | Does not compact or discard to satisfy the allocation request. | ||
| GMEM_NODISCARD | Does not discard to satisfy the allocation request. | ||
| GMEM_NOT_BANKED | Allocates non-banked memory. Cannot be used with GMEM_NOTIFY. | ||
| GMEM_NOTIFY | Calls the notification routine if the memory object is ever discarded. | ||
| GMEM_ZEROINIT | Initializes memory contents to zero. | ||
| Choose GMEM_FIXED or GMEM_MOVEABLE, and then combine others as needed by using the bitwise OR operator. | |||
| dwBytes | DWORD Specifies the number of bytes to be allocated. | ||
The return value identifies the allocated global memory if the function is successful.
Otherwise, it is NULL.
If this function is successful, it allocates at least the amount requested. The actual amount allocated may be greater, and the application can use the entire amount. To determine the actual amount allocated, call the GlobalSize function.
The largest block of memory that an application can allocate is 1 MB in standard mode and 64 MB in 386 enhanced mode.