sliceAlloc
Allocates a block of memory from the libc allocator.
The block address handed out can be expected to be aligned to at least 1 * sizeof (void*).
Since GLib 2.76 this always uses the system malloc() implementation internally.
Return
a pointer to the allocated memory block, which will be null if and only if @mem_size is 0
Since
2.10
Parameters
blockSize
the number of bytes to allocate