malloc_trim
Section: C Library Functions (3)
Updated: 2022-12-15
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NAME
malloc_trim - release free memory from the heap
LIBRARY
Standard C library
(libc, -lc)
SYNOPSIS
#include <malloc.h>
int malloc_trim(size_t pad);
DESCRIPTION
The
malloc_trim()
function attempts to release free memory from the heap
(by calling
sbrk(2)
or
madvise(2)
with suitable arguments).
The
pad
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
sbrk(2).
RETURN VALUE
The
malloc_trim()
function returns 1 if memory was actually released back to the system,
or 0 if it was not possible to release any memory.
ERRORS
No errors are defined.
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
| Interface | Attribute | Value
|
|
malloc_trim()
| Thread safety | MT-Safe
|
STANDARDS
This function is a GNU extension.
NOTES
Only the main heap (using
sbrk(2))
honors the
pad
argument; thread heaps do not.
Since glibc 2.8 this function frees memory in all arenas and in all
chunks with whole free pages.
Before glibc 2.8 this function only freed memory at the
top of the heap in the main arena.
SEE ALSO
sbrk(2),
malloc(3),
mallopt(3)
Index
- NAME
-
- LIBRARY
-
- SYNOPSIS
-
- DESCRIPTION
-
- RETURN VALUE
-
- ERRORS
-
- ATTRIBUTES
-
- STANDARDS
-
- NOTES
-
- SEE ALSO
-
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Time: 01:14:26 GMT, April 19, 2024