Page 92 - DCAP408_WEB_PROGRAMMING

Windows Programming

Notes SIZE BlockSize
);
Parameters:
MemoryPool
It defines the address of memory pool to be initialized.
MemorySize
It indicates the total size of the memory.

BlockSize
It indicates the size of the memory block that will be allocated.
Return value:

TRUE on success or FALSE on failure.
Description:
Function initializes memory pool, for particular memory address. The memory address must
be passed to stFixedMemAlloc and stFixedMemFree functions to assign memory blocks in this
memory. Size of the every allocated block is at all times fixed. This function does not set the last
error code on failure. Access to the fixed memory is never coordinated. If it is mandatory it
should be implemented.
Function will be not compiled when functions accountable for memory management are disabled,
by setting ST_USE_FIXMEM for 0.

Task Make distinction between stFixedMemFree function and stFixedMemInit function.

Self Assessment

Fill in the blanks:

6. .................... blocks allocation algorithm has been established to permit technique of memory
allocation in static time, separately to number of allocated blocks.
7. The .................... constant comprises information whether functions for fixed size memory
blocks allocation are incorporated or expelled from compilation.

5.4 Changing the Size of a Memory Block

Frequently you do not know for certain how large a block you will eventually need at the time
you must start to use the block.

Example: The block might be a buffer that you use to hold a line being read from a file;
regardless of how long you make the buffer originally, you may encounter a line that is longer.
You can make the block longer by calling realloc. This function is affirmed in ‘stdlib.h’.

Function: void * realloc (void *ptr, size_t newsize)
The realloc function modifies the size of the block whose address is ptr to be newsize.

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