PurgeSpace
long *totalSize ; receives total bytes after purge
long *contigSize ; receives size of largest block after purge
PurgeSpace is a quick way to check heap status as if a general purge were to
occur. It does not actually perform the purge.
totalSize is the address of a long. Upon return, it will contain the total
number of bytes that would be available if a purge were to take place
(the current free space plus any space gained by purging).
contigSize is the address of a long. Upon return, it will contain the size, in
bytes of the largest block that would be available if a purge were to
take place.
Returns: none
block of memory. Since it does not actually purge any blocks, there will be
no time lost purging and then regenerating purged blocks.
potentially available space, but for a hypothetical compaction, rather than a
conjectural purge. A typical sequence before allocating a large block might
look like:
long bytesNeeded, totalBytes, contigBytes;
if ( MaxBlock() < bytesNeeded ) { /* compacting enough?*/
PurgeSpace( &totalBytes, &contigBytes );
if ( contigBytes < bytesNeeded) { /* purging enough? */
. . . allocation is very likely to fail . . .
}
}
if ( myHandle == 0 ) {
. . . allocation failed . . .
}
Note that the combination of compacting and purging that takes place when
a block is actually allocated may exceed the larger of the values returned by
consideration by either call, so you may need to call PurgeMem as a last
resort, anyway.