Section: Linux Programmer's Manual (3)
malloc_trim - release free memory from the top of the heap
int malloc_trim(size_t pad);
function attempts to release free memory at the top of the heap
with a suitable argument).
argument specifies the amount of free space to leave untrimmed
at the top of the heap.
If this argument is 0, only the minimum amount of memory is maintained
at the top of the heap (i.e., one page or less).
A nonzero argument can be used to maintain some trailing space
at the top of the heap in order to allow future allocations
to be made without having to extend the heap with
function returns 1 if memory was actually released back to the system,
or 0 if it was not possible to release any memory.
No errors are defined.
For an explanation of the terms used in this section, see
This function is a GNU extension.
This function is automatically called by
in certain circumstances; see the discussion of
This function cannot release free memory located at places
other than the top of the heap.
This function releases only memory in the main arena.
This page is part of release 4.16 of the Linux
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