FromBuffer utility to create *Buffer.

HasAccess tests if a caller can access a file with permissions `perm` in mode `mask`.

NewBuffer returns a buffer with sz number of bytes.

NewLeakyBuf creates a leaky buffer which can hold at most n buffer, each with bufSize bytes.

NewNativeBuffer utility to create *Buffer of given size with nativeEndian.

ReadBuffer utility to create *Buffer from slice of bytes.

err默认为syscall.Errno, 当不能转换时返回syscall.ENOTSUP.

Buffer is a buffer to read/write integers.