Returns a binary format that reads a binary value. If {0} is specified, the binary value will contain that many bytes. If ...

Returns a binary format that reads a binary value.  If {0} is specified, the binary value will contain that many bytes.  If {0} is not specified, the binary value will contain the remaining bytes.  The {0} can be specified either as a number, or as a binary format of the length that preceeds the binary data.