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26 .TH MALLOC_TRIM 3 2017-09-15 "Linux" "Linux Programmer's Manual"
28 malloc_trim \- release free memory from the top of the heap
30 .B #include <malloc.h>
32 .BI "int malloc_trim(size_t " pad );
36 function attempts to release free memory at the top of the heap
39 with a suitable argument).
43 argument specifies the amount of free space to leave untrimmed
44 at the top of the heap.
45 If this argument is 0, only the minimum amount of memory is maintained
46 at the top of the heap (i.e., one page or less).
47 A nonzero argument can be used to maintain some trailing space
48 at the top of the heap in order to allow future allocations
49 to be made without having to extend the heap with
54 function returns 1 if memory was actually released back to the system,
55 or 0 if it was not possible to release any memory.
57 No errors are defined.
59 .\" Available already in glibc 2.0, possibly earlier
61 For an explanation of the terms used in this section, see
67 Interface Attribute Value
70 T} Thread safety MT-Safe
74 This function is a GNU extension.
76 This function is automatically called by
78 in certain circumstances; see the discussion of
85 This function cannot release free memory located at places
86 other than the top of the heap.
88 This function releases only memory in the main arena.
89 .\" malloc/malloc.c::mTRIm():
90 .\" return result | (av == &main_arena ? sYSTRIm (pad, av) : 0);