pub unsafe fn usable_size<T>(ptr: *const T) -> usize
Expand description

Return the usable size of the allocation pointed to by ptr.

The return value may be larger than the size that was requested during allocation. This function is not a mechanism for in-place realloc(); rather it is provided solely as a tool for introspection purposes. Any discrepancy between the requested allocation size and the size reported by this function should not be depended on, since such behavior is entirely implementation-dependent.


ptr must have been allocated by Jemalloc and must not have been freed yet.