Section: Linux Programmer's Manual (3)
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malloc_usable_size - obtain size of block of memory allocated from heap
size_t malloc_usable_size (void *ptr);
function returns the number of usable bytes in the block pointed to by
a pointer to a block of memory allocated by
or a related function.
returns the number of usable bytes in
the block of allocated memory pointed to by
is NULL, 0 is returned.
Multithreading (see pthreads(7))
function is thread-safe.
This function is a GNU extension.
The value returned by
may be greater than the requested size of the allocation because
of alignment and minimum size constraints.
Although the excess bytes can be overwritten by the application
without ill effects,
this is not good programming practice:
the number of excess bytes in an allocation depends on
the underlying implementation.
The main use of this function is for debugging and introspection.
This page is part of release 3.74 of the Linux
A description of the project,
information about reporting bugs,
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- RETURN VALUE
- Multithreading (see pthreads(7))
- CONFORMING TO
- SEE ALSO