Allocating and Freeing Memory
| Function | Header File | Description |
| _alloca | stdlib.h malloc.h builtin.h |
Temporarily allocates storage space from the program's stack. |
| calloc | stdlib.h malloc.h |
Reserves storage space for an array and initializes the values of all elements to 0. |
| _debug_calloc | stdlib.h malloc.h |
Allocates memory and initializes it to 0, checks the heap, and stores information about the allocation. |
| _debug_free | stdlib.h malloc.h |
Releases memory, checks the heap, and stores information about the operation. |
| _debug_heapmin | stdlib.h malloc.h |
Returns unused memory in the heap to the operating system, and stores information about the operation. |
| _debug_malloc | stdlib.h malloc.h |
Allocates memory and initializes it to 0xAA , checks the heap, and stores information about the allocation. |
| _debug_realloc | stdlib.h malloc.h |
Changes the size of an allocated memory block, sets unused memory to 0xAA , checks the heap, and stores information about the operation. |
| stdlib.h malloc.h |
Allocates tiled memory and initializes it to 0, checks the heap, and stores information about the allocation. | |
| stdlib.h malloc.h |
Releases tiled memory, checks the heap, and stores information about the operation. | |
| stdlib.h malloc.h |
Returns unused memory in the tiled heap to the operating system, and stores information about the operation. | |
| stdlib.h malloc.h |
Allocates tiled memory and initializes it to 0xAA , checks the heap, and stores information about the allocation. | |
| stdlib.h malloc.h |
Changes the size of an allocated tiled memory block, initializes unused memory to 0xAA , checks the heap, and stores information about the operation. | |
| _debug_ucalloc | stdlib.h malloc.h |
Allocates memory from a specified heap and initializes it to 0 , checks the heap, and stores information about the allocation. |
| _debug_uheapmin | stdlib.h malloc.h |
Returns unused memory from a specified heap to the operating system, and stores information about the operation. |
| _debug_umalloc | stdlib.h malloc.h |
Allocates memory from a specified heap and initializes it to 0xAA, checks the heap, and stores information about the allocation. |
| free | stdlib.h malloc.h |
Frees storage blocks. |
| _heapmin | stdlib.h malloc.h |
Returns all unused memory from the runtime heap to the operating system. |
| malloc | stdlib.h malloc.h |
Allocates memory blocks. Reserves storage blocks. |
| realloc | stdlib.h malloc.h |
Changes storage size allocated for an object. |
| stdlib.h malloc.h |
Allocates tiled memory and initializes it to 0. | |
| stdlib.h malloc.h |
Releases tiled memory. | |
| stdlib.h malloc.h |
Returns all unused memory from the tiled runtime heap to the operating system. | |
| stdlib.h malloc.h |
Allocates a block of tiled memory. | |
| stdlib.h malloc.h |
Changes the size of an allocated tiled memory block. |
Heap Information and Checking
| Function | Header File | Description |
| _dump_allocated | stdlib.h malloc.h |
Writes information about currently allocated memory blocks. |
| _dump_allocated_delta | stdlib.h malloc.h |
Writes information about currently allocated memory |
| _heap_check | stdlib.h malloc.h |
Validates all allocated memory blocks. |
| _heapchk | malloc.h | Validates all allocated and freed objects on the default heap. |
| _heapset | malloc.h | Validates all allocated and freed objects on the default heap, and sets all free memory to a specified value. |
| _heap_walk | malloc.h | Returns information about allocated and freed objects on the default heap. |
| _mheap | umalloc.h | Finds out which heap an object was allocated from. |
| _msize | stdlib.h malloc.h |
Returns the size of an allocated block. |
| stdlib.h malloc.h |
Writes information about currently allocated memory blocks from the tiled heap. | |
| malloc.h | Writes information about currently allocated memory blocks from the tiled heap since the last call for this information. | |
| stdlib.h malloc.h |
Validates all allocated blocks of tiled memory. | |
| _udump_allocated | umalloc.h | Writes information about currently allocated memory blocks from a specified heap. |
| _udump_allocated_delta | umalloc.h | Writes information about currently allocated memory blocks from a specified heap since the last call for this information. |
| _uheap_check | umalloc.h | Validates all allocated memory blocks from a specified heap. |
| _uheapchk | umalloc.h | Validates all allocated and freed objects on a specified heap. |
| _uheapset | umalloc.h | Validates all allocated and freed objects on a specified heap, and sets all free memory to a specified value. |
| _uheap_walk | umalloc.h | Returns information about allocated and freed objects on a specified heap. |
| _ustats | umalloc.h | Gets information about a specified heap. |
Heap Creation and Management
| Function | Header File | Description |
| _uaddmem | umalloc.h | Adds memory to a specified heap. |
| _uclose | umalloc.h | Closes a heap so it can no longer be used. |
| _ucreate | umalloc.h | Creates a heap of memory. |
| _udefault | umalloc.h | Changes the memory heap used as the default heap. |
| _udestroy | umalloc.h | Destroys a heap. |
| _uopen | umalloc.h | Opens a heap so it can be used. |
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Alphabetical Listing of IBM C and C++
Compilers Functions and Macros